对美棉P.D.种质系的研究

Studies on American Cotton PD Germplasm lines

陆地棉P.D.种质系是美国南卡罗来纳州农业试验站选育的、皮棉产量和纤维品质得到同步改良的、遗传基础丰富的种质材料.1983年,由中国农科院棉花研究所引入我国.1985年从中棉所引入我院.1985—1987年三年的研究结果表明:这些种质系在石河子的主要表现是长势稳健,株型较紧凑,结铃性好,成熟偏晚;具有铃大(5克以上),衣分高(40%左右),衣指高等特点.更重要的是这些P.D种质系具有优良的纤维内在品质.两年的测定表明:参试的P.D系绝大多数2.5%的跨长(相当于主体长度),在30毫米上下,有些种质系的2.5%跨长达33毫米以上.高纤维强度是这些种质系的共同特点,参试材料中的绝大多数的断裂比强度均在21克/特克斯以上.麦克隆值是纤维细度和成熟度的综合指标.两年的测定表明,参试材料中,除1985年有两个系的麦克隆值分别偏低和偏高不符合标准外,其余所有测定数据均在陆地棉麦克隆值的保证范围(3.5—4.9)以内.此外,这些种质系的棉子中所含的粗蛋白(%)和粗脂肪(%)均较高,这符合生化育种的要求.

PD germplasrn Lines were developed by south Carolina Agricultural Experiment station. USA. by means of modified intermating and selection, which is the successful method of simultaneously improving lint yield and fiber quality in Cotton. These germplasrn lines has not only the high lint but also has the excellent fiber properties, especially high fiber strength, therefor, its material are Valuable to cotton breeding. In 1983, those germplasm lines were introducd to our Country by Cotton Research., Institute CAAS. In 1985, it was introduced to shihezi Agricultural College 1985 -1987, we planted those P D germplasm lines at the agricultural experiment station of our college, and studied their major agronomic and economic characters and biological features. The result of the experiment is as follows: P D. germpasm lines were better adapted to the natural condition in shihezi, cmpared with check cultivar Xinlouzao-1, P D. germplasm lines are wider or sight wider in cotton plant form, and later in maturing. All PD lines have the weightier boll size (over 5 grams), higher lint percentage (about 40%), weight lint index and seed index. Two lint samples of each PD linse as well as Xinlouzao-1, picked from cotton plants grown at Shihezi during 1985 and 1987, were measured with HVI900 System instruments. The result of the determination shows that the fiber quality of PD. linesis either excellent or good. The 2. 5%fiber span length of all samples of PD lines were about 30 millimeters; some of them reached 33 millimeters or more. PD. germplasm lines have the High fiber strength; most of the fiber strength were over 21 g/ tex, some sample reached23 g/tex or more. Micronair value is a synthetical index of fiber fineness and maturity, which plays an important role in determining the market value of cotton lint. The premium range of micronair value for upland cotton is from 3. 5 - 4. 9 units. The result of determination shows that the micronair value of most of PD. germplasm lines ranges from 3. 5 - 4. 9units.