Correlation between derived weather parameters and crop parameters as influenced by land configuration, herbicide and plant geometry under polyethylene film mulched groundnut (Arachis hypogaea L.)

Abstract

Crop parameters, namely, dry matter production (DMP), mature pods/plant, pod yield and harvest index (HI) were recorded in a field experiment repeated in the autumn of 2001 and in the winter of 2001 – 2002 and in another set of experiments repeated in autumn 2002 and winter 2002 – 2003 to study the crop-weather relationship in polyethylene film mulched groundnut. The crop parameters were correlated with derived weather parameters, namely, Growing Degree Days (GDD), Heat Unit Efficiency (HUE), Relative Temperature Disparity (RTD), Relative Humidity Disparity (RHD) and with soil temperatures recorded at three depths (10, 20 and 30 cm). The correlations and regressions obtained in the first experiment revealed that soil temperatures in the 10 cm depth layer are ineffective to groundnut production in the autumn, while they are advantageous in winter. In the second experiment, a lower soil temperature up to 20 cm depth resulted favorable for autumn groundnut, while for the winter crop a better production is obtained with higher soil temperatures in the first 10 cm of depth. In the autumn 2001, except HI, all other crop parameters were positively correlated with weather parameters, while during winter 2002, on the contrary, all crop parameters were negatively influenced by GDD, RTD and RHD, and positively by HUE. In the second experiment, HI showed a significant positive correlation with HUE during winter 2002 – 2003, but it was negative in autumn 2002.

Keywords:

• Soil temperature
• Growing Degree Days (GDD)
• Heat Unit Efficiency (HUE)
• Relative Temperature Disparity (RTD)
• Relative Humidity Disparity (RHD)
• groundnut
• polyethylene films