Influence of Weather Parameters and Thermal Time Approach on Green Gram at Coimbatore, Tamil Nadu

An investigation was carried out at the Agro Climate Research Centre, Tamil Nadu Agricultural University, on the effect of weather parameters on the green gram yield sown at various sowing dates during the rabi season of 2019. At various sowing dates, two green gram cultivars, VBN 4 and ADT 3, were sown. For both cultivars, the phonological crop length decreased with delays in sowing dates beyond October 23rd. The yield of green gram sown on 23rd October was significantly higher than the crops sown on 30th October and 6th November. The weather parameters Maximum Temperature (Tmax), Diurnal Range (Trange), Bright Sunshine Hours (BSS), Relative Humidity (RH I), Wind Speed (WS) were found to be negatively correlated with seed yield whereas Minimum Temperature (Tmin), Relative Humidity (RH II), Vapour Pressure (VP) were found to be positively correlated with the yield of green gram. The accurate prediction of green gram yield could be done with the maximum temperature, bright sunshine hours, wind speed and with thermal indices especially hygrothermal unit II with 82 percent, accuracy level

An Integrated Effect of Weed Management in Blackgram

A field experiment was conducted at Wetlands farm, Department of Agronomy, Tamil Nadu Agricultural University, Coimbatore during summer season (March-June) of 2023, to study the effect of different weed management practices on weed flora, weed growth and yield of summer irrigated blackgram (VBN11). The field experiment was laid out in Randomized Block Design with nine treatments and three replications. Treatments comprised of power operated weeder  at 15 DAS and 30 DAS with 40 × 7.5 cm and 45 × 7.5 cm plant spacing; pre-emergence application of  pendimethalin 30% EC @ 1 kg ha-1 fb (followed by) power operated weeder at 20 DAS with 40 × 7.5 cm and 45 × 7.5 cm plant spacing; pre-emergence application of pendimethalin 30% EC @1 kg ha-1 fb early post emergence application of Imazethapyr @ 100 g ha-1 + Quizalofop-ethyl @ 50 g ha-1 (Tank mix) at 20 DAS  with 40 × 7.5 cm plant spacing and 45 × 7.5 cm plant spacing; hand weeding at 20 DAS and 40 DAS with 30 × 10 cm plant spacing. The results revealed that among the various weed management practices, the weeds were effectively controlled by the pre-emergence application of pendimethalin 30 % EC @ 1 kg  ha-1fb power weeder at 20 DAS with 40 × 7.5 cm plant spacing with significantly lower weed density, higher Weed Control Efficiency and higher grain yield (881 kg ha-1)