Influence of Different Sowing Dates on Growth Period and Yield of Early Rice in the Pearl River Delta Region
Wang Guanglun
Zhang Liuhong
Wang Hua
Liu Ye
Abstract：This study aims to clarify the response of the growth period and yield of early rice in the Pearl River Delta region to changes in climate factors with different sowing dates,and to provide a scien-tific reference for the rational arrangement of early rice sowing dates to achieve high yields in the region.Based on the staged sowing experiment at the Guangdong Agricultural Meteorological Experimental Station from 2018 to 2021,the response characteristics of yield components,including the length of growth peri-od,yield,effective panicle number,grain number per panicle,seed setting rate,and thousand grain weight of the conventional early rice variety"Yefengzhan"to climate factors under different sowing dates are studied by means of correlation coefficient and variation coefficient,etc.The results show that:(1)With the delay of sowing dates,the average temperature during the growing season of early rice increases,the growth period is shortened,and the variation range of the growth period is smaller than that of the so-wing dates.The yield of early rice is positively correlated to the average temperature during the rice-grow-ing season,effective accumulated temperature ≥ 10 ℃ and accumulated sunshine hours,but negatively correlated to precipitation.Among them,sunshine hour is the major climatic factor affecting early rice yield in the Pearl River Delta region.(2)The high-to-low order of the influence of sowing dates on rice yield components is:effective number of ears≥number of grains per ear ≥ seed setting rate≥thousand grain weight.As the sowing date is delayed,the number of effective ears tends to increase,while the number of grains per ear tends to decrease.The setting rate and thousand grain weight tend to increase first and then decrease.(3)The second and third sowing dates of the experimental year are relatively high-yielding for early rice,and the third sowing date has the least impact on yield fluctuation.The suit-able sowing date for early rice should be postponed appropriately.It is recommended that the sowing date of early rice in the Pearl River Delta region be arranged in the mid-March.
Keywords：early ricesowing dateclimatic factorgrowth periodyieldPearl River Delta region
Publication Date：2025-07-30
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 35-42 )