Field experiments were conducted at the Directorate of Rice Research experimental farm, ICRISAT campus, Patancheru, Hyderabad, during 1998-2000 for five consecutive seasons (three wet and two dry seasons) with five treatments [T1 -100 % straw incorporation; T2 -50 % straw incorporation; T3 -100 % straw + green manure (GM) incorporation; T4 -100 % straw burning and T5 -100 % straw removal (control)] along with the recommended dose of fertilizers to evaluate the effect of different crop residue management (CRM) practices on yield components and yield of rice in rice-rice cropping sequence. The ammonium N measured at active tillering was higher in 100 % straw-added plots over 50 % straw addition and straw removal with maximum values in the straw + GM-incorporated plots. Among the yield components, tillers, panicles and spikelets were influenced from the second season of residue incorporation with significant increase in 100 % straw-added treatments. The increase in tiller and panicle number could be attributed to the increased NH 4 -N in these treatments, which is evident from the significant correlation between tiller number and NH 4 -N (r ¼ 0.82**) and panicle number and NH 4 -N (r ¼ 0.87**). The influence of residue treatments on rice grain yield was observed from the third season onwards where incorporation of straw alone or in combination with GM and burning of straw significantly increased grain and straw yields. Grain yield showed significant positive correlation with the number of tillers (r ¼ 0.74*-0.81**) and panicles (r ¼ 0.74*-0.84**) in three treatments (T1, T3 andT4) where grain yields were significantly higher. The regression analysis showed that 57-66 % and 64-75 % of the variation in yield could be explained by tillers and panicles together in these three treatments during wet and dry seasons respectively. Thus, CRM practices such as addition of 100 % straw either alone or with GM and straw burning influenced the yield components (tillers, panicles and spikelets) positively and thereby increased rice grain yields.

Field experiments in vertisols of low, medium and high available soil phosphorus status were conducted to study the response of graded levels of P application to sunflower hybrid (KBSH-1). Effect of P to sunflower in increasing yield and yield attributes was more pronounced in low P status soil. Response equations for seed yield of sunflower at an applied P level have been worked out. Nutrient use efficiency and productive efficiency were also computed. Soil available P status was found to vary significantly only in low P status. Critical P level in soil was found to be 20 kg P ha-1 , below which sunflower may respond to phosphorus application.

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The present study screened bacteria isolated from rice rhizosphere for various beneficial traits related to three categories of plant growth promotion, abiotic stress tolerance, and compatibility with multiple agrichemicals to identify a microbial consortium that performs better than individual isolates in improving rice growth under normal and stressful environmental conditions. Among thirty-two isolates screened, 29, 9, 20 isolates were able to solublilize insoluble minerals of nutrients like phosphorous, potassium and zinc respectively. About 29, 31, 23, 17 isolates were found to possess the traits of IAA, ammonia, siderophore and HCN production respectively. Abiotic stress related traits of salinity, drought and high temperature tolerance were displayed by 8, 2 and 10 isolates respectively when examined for their growth in NaCl (4%, 6% 8%), in PEG (64 g/l equivalent to -0.73Mpa) and at 45℃ temperature. Agrichemical tolerant isolates were identified by screening for compatibility with fertilizers and commonly used rice pesticides. Based on the scores assigned during screening tests, 9 best isolates, three from each category, were selected for development of consortia. Our aim in this initial study was to identify three consortia (C-1, 2 and 3) consisting of three compatible bacteria, and to evaluate their effect on rice seed germination and seedling  growth under normal in vitro conditions. C1 enhanced the growth of rice when compared with individual strains, C2 and C3 with highest vigour index I, II values of 1616 ± 18 and 5.47 ± 0.68 respectively. The 16S rRNA sequence analysis identified the bacterial isolates in C1 as Achromobacter sp, Stenotrophomonas sp and Pseudomonas stutzeri. Therefore, this study has identified a unique consortium that can be used for rice growth promotion while simultaneously demonstrating the advantage of bacterial consortia over single isolate inoculants under non stressed conditions.

Aim: To determine the response of seed priming and nitrogen levels on yield and yield attributes of sunflower under zero till conditions succeeding rice. Study Design: Split plot. Place and Duration of Study: Krishi Vigyan Kendra, Palem, between December 2021 and  March 2022. Methodology: A field experiment was conducted at Krishi Vigyan Kendra, Palem, Nagarkurnool (District) during rabi 2021-22 to assess the effect of seed priming and nitrogen management on growth and yield of zero till sunflower (Helianthus annuus L.) succeeding rice. The experiment was assigned in twelve treatments, laid out in split plot design with three replications. Treatments included were 4 treatments of seed priming methods (i) M1 = Control (no priming) (ii) M2 = Hydropriming (iii) M3 = Osmopriming with KNO3 @ 0.1% (iv) M4 = Osmopriming with NaCl @ 0.1% and 3 nitrogen levels (i) S1 = 100% RDN (ii) S2 = 100% RDN (iii) S3 = 150% RDN (RDN randomly placed in sub plots of the main plot. Results: The results revealed that head diameter (16.4 cm), number of seeds per head (534), threshing percentage (79.0%) and seed yield (1961 kg ha-1) of zero till sunflower was significantly higher in osmopriming of seeds with KNO3 @ 0.1% over other treatments. Among nitrogen levels, head diameter (16.1 cm), number of seeds per head (551), threshing percentage (79.7%) and seed yield (1944 kg ha-1) of zero till sunflower was significantly higher under with application of 150% RDN over 100% RDN and 125% RDN. Conclusion: Adoption of seed priming with KNO3 @ 0.1% for 12 hours and applying nitrogen @ 150% RDN improves the head diameter, number of seeds per head, threshing percentage which in turn increased the rabi sunflower seed yield under zero tilled conditions succeeding to rice.