Heterosis breeding, general and specific combining ability and stability studies in pearl millet: Current trends

181 Caccam et al. Int. J. Biosci. 2025 RESEARCH PAPER RESEARCH PAPERRESEARCH PAPER RESEARCH PAPER OPEN ACCESS OPEN ACCESSOPEN ACCESS OPEN ACCESS Mulberry ( Morus alba L.) farming systems: Impact on silkworm growth and cocoon production in northern Philippines Mabel M. Caccam * , Josephine A. Guiner, Roel D. Supsup, Jarson P. Libunao, Evangel M. Barrameda Don Mariano Marcos Memorial State University, Bacnotan, La Union , Philippines Key words: Silkworm, Mulberry, LEISA, Organic farming, Biofertilizer, Farming practices http://dx.doi.org/10.12692/ijb/26.4.181-197 Article published on April 13, 2025 Abstract Sustainable farming practices using LEISA and Organic Farming combined with biofertilizers were evaluated to improve sericulture farm productivity and profitability of sericulture farms in Northern Philippines. Growth and yield parameters for silkworms were gathered; tabulated and analyzed using Combined ANOVA (RCBD) and means were compared using HSD. Cost-returns was also estimated. Three systems were found productive: LEISA + biofertilizer 2, Biofertilizer 1, and Organic + Biofertilizer 2 as indicated by heavier 10 mature larvae, higher effective rearing rates and consequently higher cocoon yield per box. Rearing seasons significantly affected the silkworm growth, yield and cocoon characters. The best seasons were during the colder months, November-December (Year 1), May-June (Year 2) and September-October (Year 2). The weight of 10 matured larvae, effective rearing rates, and cocoon yield per box were significantly influenced by the farming systems at each level of rearing seasons. Higher net income and return on investment (main and combined products) were recorded in LEISA + Biofertilizer 1 and Biofertilizer 2, Organic farming + Biofertilizer 1 and Biofertilizer 2 compared with cocoons raised in conventional practices. * Corresponding Author: Mabel M. Caccam  mcacca[email protected] International Journal of Biosciences | IJB | ISSN: 2220-6655 (Print) 2222-5234 (Online) http://www.innspub.net Vol. 26, No. 4, p. 181-197, 2025 182 Caccam et al. Int. J. Biosci. 2025 Introduction Sericulture in the Philippines should be rigorously pursued to meet local and international demands for silk fabrics and other allied products. With the strong support of government agencies and funding support of international institutions, sericulture is one of the agro-based industries that could boast economic growth for farmers owing to still vast land to cultivate suitable climate and available manpower and resources to perform enormous activities in both agricultural and industrial phase of the industry. International institutions (Japanese govt), also provide funds/grant to promote sericulture production in the Philippines (Mabesa, 2019). Despite these potentials, silk production is low to meet local demands. Sericulture in Region I is conventionally farmed using inorganic fertilizers, pesticides and fossil fuel for irrigation among others. With increasing inflation rates and soaring prices of the inputs and labor, farmers can no longer apply the needed requirements of mulberry plants for plant growth and development. In CY 2022, extension reports revealed low farm productivity and profitability due to low quality mulberry leaf and cocoon yield because of the presence of weeds, low soil fertility, limited water supply and high pest and disease incidence (SRDI Annual Report, 2022). To improve farm production and income, measures should be in line with the Sustainable Development Goals of the of the United Nations, to end poverty and hunger, achieve food security and improved nutrition and promote sustainable agriculture, promote sustained, inclusive and sustainable economic growth, full and productive employment and decent work for all, among others. To achieve these, new farming systems were designed and employed using the Low External Input Sustainable Agriculture (LEISA) and organic farming in place of the conventional farming practices. The LEISA techniques involved the use of sustainable technologies such as waste recycling (composting), biofertilization, and use of green manures instead of chemical fertilizers. This was to avoid if not eliminate the adverse effect of continuous use of chemical fertilizer on the soil, human and environment. The application of plant nutrients through recycling of sericulture farm wastes as composts, vermicomposts and balance use of chemical fertilizers can facilitate quality leaf production for a better and sustainable silkworm cocoon production due to the presence of major and minor plant nutrients. Silk wastes composed of silk litters and leaf scraps when composted and applied into the soil are good sources of fertilizer. The application of reduced doses of nitrogen and phosphorus supplemented by various types of organic manures attributed cocoon yield and other economic characters of rearing and reeling at par with the control. Hence, the package comprises of Arbuscular mycorrhiza (AM) fungi-inoculated saplings variety S1, green manuring with Crotalaria juncea during rainy season and leguminous cover crop with Ligna umbellata during winter season along with the application of 50% reduced doses of N and P and full dose of K may be recommended for quality leaf yield, successful silkworm rearing and lower expenditure in mulberry cultivation under rainfed alluvial soil conditions (Saha et al., 2006). In organic farming, composting of sericulture wastes has been advocated by many workers to prevent the spread of silkworm diseases including Pebrine, Nuclear Polyhedrosis Virus (NPV) and Cytoplasmic Polyhedrosis Virus (CPV). It has been known that Pebrine spores become inactive at temperatures 55 to 60 o C (Das et al., 1990). On the other hand, biofertilizers sustain soil fertility resulting in increased crop yield without causing any environmental, water or soil hazards. VAM fungi in association with higher plants play an important role in phosphorus nutrition and increase plant growth and yield, similarly to VAM and PSM, the Phosphobacterium. When applied to the soil, it solubilizes the insoluble phosphorus in the soil to make it available to the plants for absorption (Dayakar, 2011). 183 Caccam et al. Int. J. Biosci. 2025 Although these practices seemed promising in improving farm productivity, the right combinations of chemical fertilizers along with organic fertilizers must be determined to create balance fertilization mixtures that could enhance the growth and development of mulberry plants at minimum cost. Hence, this study that aimed to determine the silkworm growth, and cocoon yield and quality when fed with leaves grown using different farming practices in different rearing seasons. It also determined the cost-returns of producing cocoons in different farming systems. Materials and methods The study was conducted at the rearing house of the DMMMSU-SRDI Grainage Building in Brgy. Sapilang, Bacnotan, La Union, Philippines. The study utilized the plantation set up of the research study on farm waste utilization in different farming practices of the Institute. Bioassay test Leaves from the different farming system practices were gathered and used in the bio-assay test as follows: A-Leaves from Conventional Farming Practices (15050-50 kg N, P 2 O 5 , K 2 0) B-Leaves from LEISA–Biofertilizer 1 (VAM) ( 75-5050 kg N, P 2 O 5 , K 2 0, + 5 t silk wastes + 5 kg VAM/ha) C-Leaves from LEISA–Biofertilizer 2 (VAMri) ( 7550-50 kg N, P 2 O 5 , K 2 0, 5 t silk wastes compost + 5 kg VAmri/ha) D-Leaves from Organic Farming Practices– Biofertilizer 1 (VAM) (10 t silk wastes compost + 10 t kakawate leaves + 5 kg VAM/ha) E-Leaves from Organic Farming practices– Biofertilizer 2 (VAMri) (10 t silk wastes compost + 10 t kakawate leaves +5 kg VAMri/ha) Preparation of the rearing house and implements The rearing house including the rearing implements such as rearing racks, rearing trays, leaf chamber, and plastic mountages were disinfected and sprayed with disinfectants three days before rearing. Other materials like paraffin papers, chicken feather, bedding and cleaning nets, silkworm bed disinfectants, and burnt rice hull were also prepared. Leaves from the different treatments were harvested in the research area (whole leaves), placed in cheese cloth bags then preserved in a leaf chamber lined with wet cloth. Silkworm rearing The silkworm larvae were brushed in a tray lined with paraffin paper using a chicken feather. The young worms were fed with chopped leaves at desired sizes for four times daily (4:00 AM; 10:00 AM, 3:00 PM and 8:00 PM) for 12 days. Proper spacing was observed before feeding the worms. Monitoring of disease occurrence was done where diseased worms were removed then properly discarded. At 3 rd instar2 nd day, 300 silkworms were counted to represent each treatment. At 4 th instar, whole leaves were fed to older worms (4 th -5 th instar larvae) for four times a day. In every instar, silkworms undergo moulting where feeding is stopped for 24-36 hours. During moulting, burnt rice hull is spread over the worms to hasten moulting. After moulting and the worms are about to resume feeding, the worms were disinfected with silkworm disinfectant. The beds were cleaned then the silkworms were transferred into new rearing trays lined with newspaper until they mature. The mature worms were then mounted into plastic mountages according to the treatments. The cocoons were harvested five (5) days after mounting. Data gathering The data gathered were as follows: Effective rearing rate (ERR, %): The final percentage survival was recorded at harvesting period. Effective rearing rate (%) = (No of cocoons that produced cocoon/ No of worms reared at third instar) × 100 Weight of 10 Matured Larvae (WTML g): 10 matured silkworms were randomly selected, weighed and recorded. 184 Caccam et al. Int. J. Biosci. 2025 Single cocoon weight (SCW, g): 10 randomly selected cocoons were weighed and recorded. Single shell weight (SSW, g): 10 randomly selected cocoons were cut to separate the shells then weighed. Cocoon yield per box (CYB -1 , kg): Computed as 20,000 worms × Effective rearing rate (ERR) × Single cocoon weight (SCW) Cocoon shell percentage (CSP, %): 10 cocoons were randomly selected and cut with a blade to separate the cocoons from the pupae. This was computed as: CSP (%) = (Cocoon shell weight/ Cocoon Weight) × 100 The treatments were laid out in Randomized Complete Block Design (RCBD) with three (3) replications. The data were recorded, tabulated, consolidated and statistically analyzed. Analysis of variance (ANOVA) in RCBD in combined analysis was used in the analysis of data using the STAR software. HSD was used in treatment comparison. All inputs and outputs were monitored and recorded in all operations from mulberry production to silkworm rearing to obtain a reliable cost-return analysis particularly on the different fertilizer treatments. Productivity and profitability were measured as follows: Net returns (PHP) = Gross income – Total expenses Return on investment (%) = (Net returns/Total production cost) × 100% Gross return was computed as production (cocoon yields) multiplied by the current price of cocoons (PHP 200.00 per kg). Total expenses included variable cost (supplies and materials and the labor cost incurred in mulberry and silkworm rearing) and the fixed cost (depreciation cost, light and water expenses). Cost of materials and labor were based on the prevailing average prices during the cropping years. Total investment included the total production cost incurred in the production systems. The data were recorded, tabulated, consolidated and subjected to cost return analysis. Results and discussion Silkworm growth, yield and quality of cocoons produced using leaves grown in different farming systems and rearing seasons. Weight of 10 matured larvae The effects of the different farming systems and rearing seasons on the weight of 10 matured larvae are reflected in Table 1. Effect of farming systems on the weight of 10 matured larvae Heavier matured larvae were recorded in LEISA + Biofertilizer 2, but comparable to cocoons raised in LEISA biofertilizer 1 and Organic Biofertilizer 1. The lightest larvae was produced in conventional practice but comparable to Organic + Biofertilizer 2 and LEISA Biofertilizer 1. This result implies that a combined use of Organic and Inorganic fertilizer + Biofertilizer VAM or Vamri and using Organic fertilizer silk wastes and green leaf manure + Biofertilizer 1 effectively improved the growth of silkworm larvae. The use of LEISA Biofertilizer 1 and Organic Biofertilizer 2 were as effective as the conventional practice in improving silkworm growth. This could be due to the combined effects of the practices that led to better silkworm growth. A biofertilizer is a substance which contains living microorganisms which, when applied to seed, plant surfaces or soil, colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the plant. The benefit of mycorrhizae to plants is mainly attributed to increased uptake of nutrients, especially phosphorus while in exchange of sugars provided by the plants. they absorb more nutrients and mobilize quickly to the plants than the root system does not have VAM association (Sakhivel et al., 2014). Both organically and conventionally 185 Caccam et al. Int. J. Biosci. 2025 produced mulberry leaves contained moisture on top and bottom that are within the acceptable range for feeding young worms that is 78-80% for the 1 st and 2 nd instar, 76-77% for the 3 rd instar, and 70% for mature worms (Caccam et al., 2015). Moisture retention capacity of the leaves was still good even after 24 hours of storage. This implies that mulberry leaves could be stored for 24 hours without impairing the quality of leaves, particularly moisture. Data show that percent moisture, ash and crude fat in top to bottom portions of leaves in organic farming are slightly higher than in conventional farming. On the other hand, percent crude fiber and crude protein were slightly higher in conventional farming than in organic farming (Caccam et al., 2015). In a study conducted by Tangamalar et al. (2018), the application of 50% Organic + 50% Inorganic fertilizer showed significantly better mulberry growth and yield parameters and consequently higher economic parameters viz. larval weight, cocoon weight, shell weight, shell ratio and effective rearing rates in both kharif and rabi seasons. Effect of rearing season on the weight of 10 matured larvae Heavier matured larvae were recorded in silkworms raised in the August-September (Year 1); November-December (Year 2); and May-June and September-October (Year 3). The lightest was recorded during the May-June (Year 1) rearing season. The colder season that starts from the onset of rainy seasons (May to December) favored the growth of silkworms). At this season, the minimum temperature for young age was 25.99 ° C, and the maximum was 28.08 ° C with a relative humidity of 82.09%. For the late age, the minimum was 26.39 ° C and the maximum was 27.87 ° C with a relative humidity of 27.87%. It was evident that the lightest matured larva was observed during May to June rearing season (Year 1) as a consequence of a higher temperature during the year. The temperatures for young age ranged from 26.27 to 28.89 ° C with an RH of 75.91%; while for late age, temperature ranged from 26.19-27.96 ° C with an RH of 84.44%. Notably, these were higher than the required temperature for late age rearing. Table 1. Weight of 10 mature larvae (g) of silkworms fed with leaves in different farming systems and seasons of rearing Rearing season Conventional LEISA+ Biof. 1 LEISA + Biof. 2 Organic +Biof. 1 Organic +Biof. 2 Season mean Nov.24 - Dec.21, 2014 26.46a - c 27.12bc 29.57a 26.45bc 25d - f 26.92b March 4 - 31, 2015 23.78cd 24.45cd 25.92b 24.05cd 21.62f 23.97c Sept. 29 - Oct. 28, 2015 26.46a - c 25.4bc 29.58a 26.45bc 25.00d - f 26.92b May 10 - June 6, 2016 22.10d 22.65d 21.06c 21.10d 22.78ef 21.94d Aug 30 - Sept 28 2016 29.39ab 28.15ab 29.78a 29.98ab 28.95ab 29.05a June 30 - July 22,2017 26.11bc 26.45bc 27.92ab 26.38bc 25.29c - e 26.43b Nov.15 - Dec. 23, 2017 28.23ab 29.37ab 29.47a 30.53a 27.03b - d 28.93a May 22 - June 12, 2018 29.72a 28.88ab 28.59ab 28.98ab 31.25a 29.48a Sept. 27 - Oct. 27, 2018 28.64ab 31.42a 28.51ab 30.13a 28.51a - c 29.44a Treatment Mean 26.77b 27.09ab 27.82a 27.22a 27.00b In a column (season means at each level of seasons), row means (treatment means) followed by the same letter are not significantly different from each other at .05 levels HSD. Comparison on treatment at each level of rearing season Analysis of variance revealed significant differences on the WTML in different rearing seasons (Table 1, Fig. 1). The WTML in conventional treatment was comparable during the rearing months of May-June and Sept-Oct (Year 5), November-December (Year 4), AugustSeptember (Year 3), September-October (Year 2) and November-December (Year 1); in LEISA + Biofertilizer 1 during the months of May-June and September-October (Year 5), November-December (Year 4), August-September (Year 3); in LEISA + Biofertilizer 2 during the months of May-June and September-October (Year 5), NovemberDecember (Year 4), August-September (Year 3), 186 Caccam et al. Int. J. Biosci. 2025 September-October (Year 2) and NovemberDecember (Year 1); in Organic Farming + biofertilizer 1 during the months of May-June and September-October (Year 5), NovemberDecember (Year 4), August-September Year 3) and Organic farming + Biofertilizer 2, during the months of May-June and September-October (Year 5), and August-September (Year 3). The results imply that the different farming systems responded differently with the different rearing seasons. However, regardless of farming systems, the best rearing seasons recorded were the months of August – September (Year 3), May-June (Year 5) and September-October (Year 5). These were the colder months of the year which favored the growth of the silkworms. Fig. 1. Weight of ten mature larvae (g) of silkworms fed with leaves in plants grown in different farming systems at each level of seasons of rearing Cropping systems: AConventional, BLEISA + Bio-fertilizer 1, CLEISA + Bio-fertilizer 2, DOrganic farming + Biofertilizer 1, EOrganic farming + Biofertilizer 2. Seasons of rearing: S1 Nov.24-Dec.21, 2014; S2 March 431, 2015; S3 Sept. 29-Oct. 28, 2015; S4 May 10June 6, 2016; S5 Aug 30-Sept 28 2016; S6 June 30July 22, 2017; S7 Nov.15-Dec. 23, 2017; S8 May 22June 12, 2018; S9 Sept. 27-Oct. 27, 2018 Effective rearing rate Effect of farming systems Effective rearing rates were significantly higher in LEISA + Biofertilizer1 and Organic Farming + Biofertilizer 2 compared to other farming systems. The lowest was observed in conventional farming but comparable to LEISA + Biofertilizer 1 and Organic Farming + Biofertilizer 1 and 2. This implies that the use of combined chemical plus organic wastes and biofertilizer and use of organic fertilizers with biofertilizers alone is effective in enhancing the survival of silkworms. Philomena et al. (2003) and Tangamalar et al. (2018) have observed higher ERR in silkworms fed with mulberry leaves grown with lower dose of inorganic fertilizer and higher doze of organic manure. This could be an attributed to a better quality of leaves in these systems (Caccam and Mendoza, 2015). The success of sericulture industry is mainly based on leaf quality and appropriate environmental conditions for silkworm rearing (Kumar et al., 2013). The effects of fertilizer management practices on leaf yield and quality of mulberry plant are important for sustainable mulberry plant production (Sultana et al., 2017). Mulberry leaves are the exclusive source of nutrition (e.g., protein, carbohydrates, vitamins, minerals, etc.) for growth and development of silkworms (Tang et al., 2005; Kumar et al., 2013). The quality of leaves 187 Caccam et al. Int. J. Biosci. 2025 fed to silkworm is considered to be the prime factor for good cocoon production (Ravikumar, 1988). Effect of rearing season The silkworms reared during the NovemberDecember (Year 4), May-June (Year 5) and September-October (Year 5) rearing season significantly had higher ERR. During these seasons, the temperature range for young age was 25.3327.71 ° C with an RH of 79.75%. For late age, the temperature range was 25.79 to 27.85 ° C and RH was 82.39%. These results corroborates with the findings of Madrid (2010) that the growth of silkworms are affected by season. December was the most favorable month for silkworm rearing which resulted to higher ERR (90.95%), and heavier silkworms (43.17 g). September rearing followed for most of the parameters except for filament length and size which were comparable to December. The crop was generally successful and the ERRs 70-80% and above indicate high yields. The lowest was observed in silkworms raised during the months of May (Year 2), May-June (Year 3), and June-July (Year 4). During these seasons, the average temperature for young age was 25.84-28.88 o C and an RH of 73.96% while for late age, the average temperature was 25.96-28.74 ° C and an RH of 76.83%. According to Pawar et al. (2016) and Caccam et al. (2018), the variations within the environmental conditions day to day and season to season emphasize the necessity of management of temperature and relative humidity for sustainable production. In this study, day to day fluctuations went as high as 26-31 ° C (10AM) and a RH of 60-72% and 26-33 ° C (3 PM) and an RH of 54-80 % and during the May (Year 2), 26-31 ° C and RH of 71-88% (AM) and 26-32.1 ° C and RH of 30-86% (PM) during MayJune (Year 3), and temperature of 26-30 ° C and RH of 75-84% (AM) and temperature of 24-31 ° C and RH of 72-84% (PM) during the June-July (Year 4) rearing season. In summer days, as temperature was very high, the silkworm could produce cocoons properly. Temperature above 30 o C directly affects the health of the worms. If the temperature is below 20 ° C all the physiological activities are retarded, especially in early instar. As a result, worms become too weak and susceptible to various diseases. The optimum temperature for normal growth of silkworms is between 20 ° C and 28 ° C and the desirable temperature for maximum productivity ranges from 23 ° C and 28 ° C (Pawar et al., 2016; Caccajm et al., 2024). Comparison of treatment at each level of seasons The effective rearing rates of silkworm were significantly influenced by the farming systems and rearing seasons. The conventional treatment had comparable effective rearing rate during the months of Nov-Dec 2014, March 2015, Nov-Dec 2017, MayJune and Sept-Oct 2018. In LEISA + bio-fertilizer 1 treatment, comparable ERR were observed during the Nov-Dec 2014, Sept-Oct 2015, Nov-Dec 2017, May-June and Sept-Oct 2018 rearing seasons while in LEISA + biofertilizer 2, it was comparable during Nov-Dec 2014, Sept-Oct 2015, May-June 2016, Aug-Sept 2016, Nov-Dec 2017, May-June 2018, Sept-Oct 2018 rearing seasons. In Organic farming + biofertilizer 1 and 2 treatments, the rearing seasons of Nov-Dec 2014, Sept-Oct 2015, May-June 2016, Nov-Dec 2017, May-June 2018, Sept-Oct 2018 that were comparable with each other were found better seasons than other rearing seasons (Table 2, Fig. 2). The result implies that the silkworms raised in different farming systems responded differently with the growing seasons. It could be noted that the best seasons for increasing survival of silkworms were the colder months of Nov–Dec 2017, May-June 2018, Sept–Oct 2018. For cocoons, ERR should be greater than 85 % for bivoltine races (Rajan et al., 2005 as cited by Caccam et al., 2024). Single cocoon weight Effect of farming systems The single cocoon weight of silkworms fed with leaves grown in different farming systems that ranged from 1.42 to 1.44 g was not significantly different with each other (Table 3). 188 Caccam et al. Int. J. Biosci. 2025 Table 2. Effective rearing rate of silkworms fed with leaves grown in different farming systems and seasons of rearing Rearing season Conventional LEISA+ Biof. 1 LEISA + Biof. 2 Organic +Biof. 1 Organic +Biof. 2 Season mean Nov.24 - Dec.21, 2014 83.00ab 76.00ab 76.33a - c 82.00ab 88.00ab 81.07bc March 4 - 31, 2015 71.00a - c 60.67bc 55.33c 47.33d 63.00c - e 59.47d Sept. 29 - Oct. 28, 2015 69.67bc 78.67ab 76.33ac 78.67ab 84.67ac 77.60c May 10 - June 6, 2016 32.00d 50c 78.67ab 47.33e 48c 51.20d Aug 30 - Sept 28 2016 69.67bc 80.33ab 83.33ab 72.33bc 72.33b - d 75.60 c June 30 - July 22,2017 57.67c 44.67c 67.33bc 53cd 58.33de 56.40cd Nov.15 - Dec. 23, 2017 92.33a 98a 98.33a 97.67a 95a 96.2a May 22 - June 12, 2018 93.00a 94.33a 95.67a 94.00ab 86.67ab 92.73a Sept.27 - Oct. 27, 2018 88.67ab 93.00a 96.67a 96.67a 92.33a 93.47a Treatment mean 73.01b 75.07b 80.88a 74.33b 76.48ab In a column (season means at each level of seasons), row means (treatment means) followed by the same letter are not significantly different from each other at .05 levels HSD. Table 3. Single cocoon weight (g) of cocoons of silkworms fed with leaves in different farming systems and seasons of rearing Rearing season Conventional LEISA+ Biof. 1 LEISA + Biof. 2 Organic +Biof. 1 Organic +Biof. 2 Season mean Nov.24 - Dec.21, 2014 1.38 1.50 1.47 1.45 1.51 1.46c March 4 - 31, 2015 1.36 1.30 1.30 1.39 1.28 1.32d Sept. 29 - Oct. 28, 2015 1.31 1.30 1.37 1.33 1.48 1.36d May 10 - June 6, 2016 1.06 1.08 1.11 0.93 1.08 1.05e Aug 30 - Sept 28, 2016 1.54 1.54 1.60 1.57 1.55 1.56b June 30 - July 22, 2017 1.68 1.70 1.71 1.76 1.68 1.71a Nov.15 - Dec. 23, 2017 1.61 1.69 1.65 1.54 1.60 1.62b May 22 - June 12, 2018 1.52 1.52 1.55 1.54 1.59 1.54bc Sept. 27 - Oct. 27, 2018 1.55 1.57 1.54 1.54 1.51 1.54bc Treatment mean 1.42 1.44 1.46 1.42 1.45 1.45 1.46 1.48 1.45 1.47 In a column (season means), means followed by the same letter are not significantly different from each other at .05 level HSD The result implies that the newly introduced farming systems did not pose any negative effects to the cocoons as it performed at par with the traditional conventional farming. Though the single cocoon weights in different farming systems felt short of the standard single cocoon weight for high production due to low cocoon yield and quality during Nov-Dec 2014 to May-June 2016 seasons very evident that on later years (Aug-Dec 2016-Sept-Oct 2018) heavier single cocoon weights were observed and within the standard range of acceptable single cocoon weight. This could be due to the effect of organic fertilizers that manifested on later years. The nutritional grade of mulberry leaves, on which the silkworm feeds, determines the health and growth of silkworm as well as the economic traits of produced silk. Thus, the amount and superiority of raw silk production and the resultant development of the sericulture sector depend on the mulberry leaves. Increasing use of organic products like vermicompost, vermiwash, farm yard manure, oil cakes, press mud plays an important role in the promotion of quality silk production (Singh, et al., 2021). Effect of rearing season Single cocoon was significantly heavier in silkworms raised during the months of June-July 2017, followed by Nov-Dec 2017, Aug-Sept 2016, May–June and Sept-Oct 2018. The temperature during this season was 25.24-27.86 ° C and RH of 77.88% for young age and 25.65-28.06 ° C and RH of 79.93% for late age rearing. These were the colder months of the year that 189 Caccam et al. Int. J. Biosci. 2025 favored the growth of silkworms to produce heavier cocoons. During the kharif season, the cocoon weight was significantly higher under 75% organic + 25% inorganic fertilizer application (Tangamahlaer et al., 2018). The lightest was observed during the months of May-June 2016 with a temp of 26.27-28.89 ° C and RH of 75.91% for young age and 26.19-27.96 o C for late age and RH 84.44 %. These could be due to the poor growth like larval weight and effective rearing rates that was observed during rearing period. The silkworms suffered from diseases that lead to poor yield and quality cocoons. Fig. 2. Effective rearing rates (%) of silkworm fed with leaves in different cropping systems at each level of seasons of rearing Cropping systems: AConventional, BLEISA + Bio-fertilizer 1, CLEISA + Bio-fertilizer 2, DOrganic farming + Biofertilizer 1, EOrganic farming + Biofertilizer 2. Seasons of rearing: S1 Nov.24-Dec.21, 2014; S2 March 431, 2015; S3 Sept. 29-Oct. 28, 2015; S4 May 10June 6, 2016; S5 Aug 30-Sept 28 2016; S6 June 30July 22, 2017; S7 Nov.15-Dec. 23, 2017; S8 May 22June 12, 2018; S9 Sept. 27-Oct. 27, 2018 Comparison of treatment at each level of seasons The single cocoon weight of silkworm was not significantly influenced by the cropping systems. The single cocoon weight ranged from 1.38 to 1.51 g during Nov-Dec 2014; from 1.28 to 1.36 g during March 2015 season; 1.30 to 1.48 g during Sept-Oct 2015; 1.06 to 1.11 g during May-June 2016; from 1.54 to 1.60 g during Aug-Sep 2016; from 1.68 to 1.76 g during June-July 2017; from 1.54 to 1.61 g during Nov-Dec 2017; from 1.51 to 1.57 g during Sept-Oct 2018 and from 1.42 to 1.46 g during the Sept-Oct 2018 rearing season. All of the farming systems had single cocoon weights that were within the standard cocoon weight (1.5 g) for high production in later years of rearing. Single shell weight Effect of farming systems The single shell weight of silkworms fed with leaves grown in different farming systems was not significantly different with each other (Table 4). The result implies that any of the farming systems could be used as an alternative to growing mulberry for silkworm rearing to produce good quality or heavier single shell. It could be advocated however that the use of LEISA and Organic fertilizers + biofertilizers could be used instead of conventional farming to eliminate the adverse effect of continues use of fertilizers and other chemical inputs. The silkworm wastes that are available in most sericulture farms and other farm wastes are nutrient rich fertilizers. The silkworm excreta, containing 7.35% water, 196 Caccam et al. Int. J. Biosci. 2025 Recommendation Suistainable practices using the LEISA + biofertilizer 1 and 2 and Organic Farming + biofertilizer 2 could be an alternative to conventional farming due to heavier weight of ten mature larvae, and higher effective rearing rates and heavier cocoon yield per box. This also resulted to higher net income and return investment. References Ahmed F, Sultana R, Ahmed O, Iqbal MT. 2017. Seriwaste compost enhances mulberry leaf yield and quality in Bangladesh. 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