Effects of Meteorological Parameters and Irrigation on Micronaire Index of Cotton in Greece
Mar 28, 2019
The influence of temperature, rainfall, relative humidity and irrigation on the micronaire value of cotton grown in Greece during the period 1986-1994 was studied. Micronaire was positively affected by temperature, mainly by daily maximum and mean temperature. Within the temperature range encountered, depending on developmental stage, an increase of 1.5 – 2.0oC increased micronaire by 0.5. The micronaire value was most influenced during stages that include the period of boll maturation and boll opening, with R2 values over 0.5 in many cases, reaching 0.9 for the boll opening and harvesting phases. The effects of rainfall and relative humidity were negative and significantly stronger during the stages from boll opening to harvesting with R2 ranging up to 0.8 for rainfall and R2 up to 0.6 for relative humidity. Addition of irrigation water to rain weakened regressions and restricted the number of stages with significant water effects. Use of multiple regression analysis, taking account of all parameters studied, resulted in higher R2 values. Micronaire values could be predicted using the models developed. The applicability of management techniques to decrease adverse or increase favourable effects of weather is discussed.