No abstract

An experiment laid down to evaluate the effect of biofertilizers, growth regulator gibbralic acid (GA3) and micronutrients on yield and yield attributes of Sapota cv. Kalipatti at Fruit Research Station, Navsari Agricultural University, Gandevi, Gujarat. The treatments of recommended dose of fertilizer (RDF), i.e.100 kg FYM and 1000:500:500 g/plant NPK along with application of biofertilizers (Azospirillum + PSB), growth regulator (GA3) and micronutrients. The pooled results of  75% RDF + biofertilizers- Azospirillum + PSB @ 40 ml/tree + GA3 @ 50 ppm + Grade 4 (micronutrient @ 0.5%) were exhibited significantly higher number of fruit (2815.45), yield (20.61 t/ha)along with net return (Rs. 3,03,951/ha) and Benefit Cost Ratio (2.81). The said application enhanced fruit yield up to 43.41% over control comprising RDF only. However, significantly higher fruit weight (81.34 g) was recorded in application of 100% RDF + biofertilizers- Azospirillum + PSB @ 40ml/tree + GA3 @ 50 ppm + Grade-4 (micronutrient @ 0.5%).

The present study was under taken to investigate the feasibility of estimating productivity of rabi sugarcane crop based on weather variables using past weather and yield records of different districts of South Gujarat. In the modeling used, it was considered as an independent variable. The generated weather variables were developed using weighted accumulation of fortnightly data on weather variable, weights being the correlation coefficient of the weather variables, in respective fortnights with the dependent variable, i.e. the yield of sugarcane yield. Forecasting models were developed using from a time series of 26 years (1995 96 to 2020-21) of weather and yield data of sugarcane crop in four Navsari, Bharuch, Surat and Tapi districts and their performance have been validated against the observed yield during 2018-19, 2019-20 and 2020-21. Results indicated that coefficient of determination (R2) values were 0.67 to 0.76 during mid-season (F1) stage and 0.76 to 0.91 during pre-harvest (F2) stage in four districts. Hence, these models can be used for forecasting sugarcane yield in preharvest stage which is very useful to government authorities to plan the sugarcane production more efficiently.

An attempt has been made to developed the pre - harvesting forecasting models for cotton yields using (1995-2020) weather and yield data for Bharuch and Surat districts respectively. Models were validated for three years (2018-2020). Good agreements have been realized between actual and predicted yield with similar trends of deviation at pre - harvest stage. R2 values were 0.78 to 0.93 for both districts and stages respectively. Hence, these models can be used for forecasting cotton yield in mid – season (F1) and pre - harvest stage (F2) which is very useful to government authorities to plan the sugarcane production more efficiently. The estimated cotton yields during kharif, the year 2022 were 769 kg/ha and 870 kg/ha for F1 & F2 stage in Bharuch district and 1209 kg/ha and 1454 kg/ha for F1 & F2 stage in Surat district, respectively.