中棉16丰产性分析及其栽培方向探讨

ANALYSIS ON THE PRODUCTIVITY OF ZHONGMIAN 16 (Gossypium hirsutum)AND ITS KEY CULTURAL TECHNIQUES

中棉16是适于麦棉两熟的丰产、稳产夏播棉新品种。经全国夏棉区试与冀、鲁、豫三省的生产试验,每公顷霜前皮棉产量612.0～856.5公斤(40.8～57.1公斤/亩),比对照增产9.1％～22.2％,均居第一位。其回归系数bi为1.22>1,回归直线居所有参试品种之上,且随环境指数的提高而明显。回归离差S_(di)~2为23.8,小于其它参试品种。经通径分析,密度的通径系数最终效应值为0.7979,达极显著水平,而单株铃数、单铃重与衣分的通径系数最终效应值均较小。中棉16的栽培方向应在适时播种的前题下.以密度为中心.科学施肥为基础,主动化调为保证。在中等地力,每公顷皮棉1125～1200公斤产量水平,适宜密度为9～15万株.施纯氮105～150公斤,五氧化二磷75～120公斤,其中,追肥占60％,整个生育期喷缩节安2～3次,每次用量15～60克,每公顷总用量53～120克。

Zhongmian 16 is a new cotton variety with higher and constant yield, which is suitable for cotton-wheat double cropping system. It has a pre-frost lint yield of 612.0~856.5 kg/hm^2, 9.1%～22.2% which is higher than that of the control, ranked first in the national, Henan and shandong summer cotton variety reginal tests and the commercial tests in Hebei, Shandong and Henan Provinces in 1988 and 1989. Its regression coefficient bi is 1.22>1. The regression line was higher than that of varieties and became obvious with the increase of environmental index. The regression deviation S_(di)~2 is 23.8, less than that of the other tested varieties. path analysis showed that the terminal path coefficient value of the plant density was 0.7979 at a very significant level, but the bolls per plant, boll weight and lint percent were not significent. Therefore, the key techniques of Zhongmian 16 should be focused on plant density, based on scientific side-dressing and chemical regulation. In normal fertile field, Zhongmian 16 with 90～150 thousand plants/hm^2. can give a lint yield of 1125～1200 kg, needing pure N 105～150 kg, P_2O_5 75～120 kg, of which side-dressing takes up 60%, and 2～3 times of DPC control with 15～60 g each application during the whole developmental period.