An experiment was conducted during 2019–20 at the Research Farm of Dr. BSKKV, Dapoli, Maharashtra to study the effect of crop residues and fertilizers on humus fractions and rice yield in Alfisols. The study was conducted on ex situ incorporation of crop residue along with fertilizers and the results indicated that application of rice straw @2.5 t/ha + Ain leaf residue @2.5 t/ha along with 100% NPK was significantly beneficial for improving the content of soil humin, humic acid, fulvic acid and humic acid : fulvic acid (HA: FA) ratio and yield of rice. Crop residue and fertilizer management significantly improved the soil humin, humic acid, fulvic acid and humic acid: fulvic acid (HA: FA) ratio. Build-up of soil humus was due to the balanced application of crop residue along with fertilizers for developing bio-stability in soil which helps maintain soil health. In contrast, the application of 50%, 75% and 100% NPK alone did not gain optimum humus content in soil and yield of rice because of unbalanced use of fertilizers. Overall improvement in soil humus and yield of rice was observed by the integrated use of crop residue along with fertilizers in Alfisols.

An in vitro trial was conducted in the Department of Entomology, Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, Dapoli, Ratnagiri, Maharashtra; to determine the compatibility of green muscardine fungus, Metarhizium anisopliae (Metachnikoff) Sorokin with pesticides and its pathogenicity against A. craccivora. Azadirachtin, Buprofezin and Sulphur were the most suitable pesticides as it showed significantly superior growth on potato dextrose agar media over untreated control. However, Emamectin benzoate, Azadirachtin, Profenophos, Indoxacarb, Thiophanate, Paraquat Dichloride and Glyphosate showed significantly higher mean mycelial weight over the untreated control on potato broth medium. At the same time, amongst pesticides used in the experiment; only insecticides (Emamectin benzoate, Azadirachtin and Deltamethrin) reported synergistic increase in conidial count with the untreated control, while fungicides and herbicides reported drastic reduction in conidial count. The pathogenicity of M. anisopliae harvested from the pesticide treatments against A. craccivora revealed that all the pesticides investigated had reduced its pathogenicity in comparison to untreated control. However Emamectin benzoate, Indoxacarb and Paraquat dichloride showed maximum per cent mortality and can be used in combination with M. anisopliae.

Nitrogen is the major nutrient plays a key role in the production of rice crop and the lateritic soils are low in available nitrogen content. Accordingly, the field study was carried out in lateritic soils of Konkan (Coastal) region during year (2017 – 2018) to find out the effect of different levels of nitrogen along with silica levels on growth and yield of rice. The major aspect behind taking this kind of research was to see the interaction between the applications of varying levels of nitrogen with the different levels of silica. An experiment was carried out with FRBD design. The nitrogen was given by the Konkan Annapurna Briquettes (KAB) which is the compressed tablet type mixture of the fertilizer which is having major nutrients N, P and K. Silica was applied solely through potassium silicate with the paper packets. There might have been positive response with growth and silica levels also with the rate of application of nitrogen with the increased levels of silica. It was observed that the application of 80 per cent RDN through Konkan Annapurna Briquettes (KAB) with Silica @ 100 kg ha-1 which was applied between four hills was found promising in enhancing the growth and yield of Ratnagiri-24 Cv. in lateritic during Kharif season. It could be concluded that, the application of nutrients in the form of Konkan Annapurna Briquettes along with the application of silica can reduce the recommended dose of fertilizer to the extent of 20 per cent during Kharif season in Konkan region.

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