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An investigation was conducted to study the effect of different plant growth regulators on growth and flowering of cucumber cv. Malini under shade net conditions. The experiment was carried out with 10 treatments GA 3 at 75, 150 and 250 ppm, Ethrel at 100, 200 and 300 ppm, Salicylic acid at 75, 150 and 250 ppm and control (water spray) in three replications. Among all, GA 3 at 75 ppm recorded with maximum vine length (271.76 cm), number of number of leaves (90.32), number of nodes on main stem (30.22), length of primary branches (153.25 cm) and leaf area (458.14 cm²), whereas, maximum number of primary branches(18.49) was recorded in ethrel 300 ppm. Further, maximum internodal distance (8.24 cm) was recorded with GA 3 at 250 ppm. With respect to phenological parameters, ethrel at 300 ppm exhibited the best results for the minimum number of days taken for first female flower appearance (38.88 days), least node number of first female flower appearance (6.77) and lowest male to female sex ratio (1.40) as compared to other treatments, whereas treatment GA 3 at 150 ppm recorded minimum number of days taken to initiation of flowering (33.74 days), minimum days taken for 50 per cent flowering (44.91 days) and time taken for first harvesting (51.80 days) over other treatments and finally yield (165.17 t/ha) was recorded highest in GA 3 75 ppm compared to other treatments.

Background: Identification of suitable factors that influence significantly to the response is crucial for the traits based breeding program to make a better decision about improvement in productivity. Multiple linear regression (MLR) is the benchmark method commonly using to identify suitable factors for crop improvement. It doesn’t work always due to stringent assumption (Multicollinearity, Linearity) behind the MLR model. Here we tried to develop an efficient model for the selection of major traits that contribute to seed yield in soybean by comparing different models.Methods: Field experiment was conducted using 98 soybean core population through augmented design.18 morphometric traits obtain from soybean core population were considered under the study as regressors.Multiple linear regression (MLR), Principle component Regression (PCR), Regression tree and Random Forest models were compared to select traits based on prediction accuracy.Result: All the models identified the number of pods per plant (NPP) has the most influencing variable to the soybean yield. However random forest has a much higher prediction power (RMSE=4.59, MAPE=0.18) compared to other models under study. The results of random forest revealed that the number of pods per plant, number of branches per plant and other associated characters like plant height at harvest as highly influencing traits for seed yield in soybean.Finally, tried to identify genotypesthat possess superiority about most influencing morphological characters on seed yield using cluster analysis.

Aim: The study was undertaken to assess the efficiency and select the virulent entomopathogenic fungal isolates for the biological control of red spider mites (Tetranychus urticae) under in vitro conditions. Place and Duration of Work: The study was carried out in the Department of Agricultural Microbiology, University of Agricultural Sciences, GKVK, Bangalore, India. Methodology: A leaf disc bioassay was employed to assess the virulence of entomopathogenic fungal isolates isolated from 2 agro-climatic zones of Karnataka, India under In vitro conditions. The lethal concentration and lethal time were determined by obtaining the mortality data from various conidial concentrations and the data was analysed using Probit analysis. For molecular identification the fungal DNA was isolated through Cetyl trimethyl ammonium bromide (CTAB) extraction buffer, followed by purification through phenol/chloroform extraction and precipitation with isopropanol or ethanol, and the ITS regions of the 18S rDNA were amplificated using universal primers. Results: Out of 81 fungal isolates, 16 (19.25%) showed insecticidal activity under in vitro conditions. The results of the in vitro studies revealed that two isolates, ENPF-8 and ENPF-58 had significantly higher mortality rates (93-95 %) against mites at a concentration of 1x108 conidia/ml after 9 days after treatment (DAT). The virulent fungal isolates were identified as Isaria fumosorosea (with accession no: MT997932) and Hirsutella thompsonii (MT997936) using the sequencing of the ITS region of the 18S rDNA gene. H. thompsonii (ENPF-58) was found to be more virulent against mites, with lower LC50 (7.6×105 conidia/ml) and LT50 (5.7, 5.89, and 5.99 days) values compared to the other EPF. Conclusion: Based on results, it is evidenced that though all isolates caused mortality in the mite population but the percent mortality was varied. Based on these results, H. thompsonii (MT997935) and Isaria fumosorosea (MT997932) could be a promising biocontrol agent due to their high virulence against mites.

Aim: The study was undertaken to evaluate agro-wastes (Post mushroom substrate, Sugarcane bagasse, rice husk and sorghum grains) for mass production of entomopathogenic fungi like, I. fumosoroseus:MT997932, B. bassiana: MT997933, L. lecanii: MT997935 and H. thompsonii: MT997936 by solid stat fermentation. Place and Duration of Work: The study was carried out in the Department of Agricultural Microbiology, GKVK, University of Agricultural Sciences, Bangalore during 2019-20. Methodology: The substrates were dried, chopped and sieved through 2mm sieve. 100g of all substrates were sterilized and moistened to 60% by adding sterile distilled water fallowed by addition of 5ml of spore suspension of fungal isolates. Treatments T5. T6, T7, T8 and T10 were fortified with adding 10ml of molasses. Observation like, growth and spore production were taken at 7, 14 and 21 days after inoculation. Results: The growth and spore production of entomopathogenic fungal isolates were observed to be increased accordance with the incubation period. Among four substrates maximum mycelial growth and spore production of all the isolates (×109 spores g-1) was observed in sorghum grains (T4:T8) fallowed by treatment T7 (SMS+10% molasses) on 21 DAI. Whereas, sugarcane bagasse and paddy husk substrates were not supported the satisfactory growth and spore production besides the addition of molasses (×107 spores g-1). The addition of molasses has positively influenced the growth and spore production of entomogenus isolates in all treatments. Conclusion: Based on results, it is evidenced that even though cereal grains are best option for mass production, PMS fortified with molasses will become a better substrate for mass production and reduce the load of using food grains as substrate.