Change in Nitrogen Content of Greenhouse Grown Cotton Bract During Senescence.

Raymer-PL; Morey-PR; Lupton-CJ

Proceedings of the Third Special Session on Cotton Dust Research, Beltwide Cotton Production Research Conference, Phoenix, Arizona, January 9-10, 1979 1979 Jan:34-35

00171990

The nitrogen content of cotton bracts during postanthesis development was investigated. The total nitrogen content of bracts from Tamcot SP21 cotton plants grown in a greenhouse was determined at 20 day intervals through 120 days postanthesis. The nitrogen content of other plant parts such as the fully expanded leaf blade, green capsule, senescent capsule, green pedicel, and senescent pedicel was also measured. The micro/Kjeldahl method was used to determine the nitrogen content of the cotton bracts. The nitrogen content of the other plant parts was determined by the macro/Kjeldahl technique. The average total nitrogen content of cotton bracts at anthesis was 2.5 percent, and this decreased to 1.0 percent after 120 days. The largest decrease occurred between 60 and 80 days. Fully expanded green leaf blades contained significantly more nitrogen than senescent leaf blades. Green capsule walls also contained more nitrogen than the senescent capsule walls. The authors conclude that since the byssinosis prevalence rate has been correlated with the nitrogen content of cotton dust and that green bracts, leaf, and capsule contain more nitrogen than their senescent counterparts, special care should be exercised, when processing unopened bolls, to remove all of the green trash fragments.

NIOSH-Grant; Chemical-analysis; Plant-substances; Cotton-industry; Nitrogen-compounds; Chemical-extraction; Biological-distribution; Chemical-composition; Physical-properties;

19790110

Conference/Symposia Proceedings;

Wakelyn-PJ;

54181.00

Grant;

1979

Grant-Number-R01-OH-00667-02

Proceedings of the Third Special Session on Cotton Dust Research, Beltwide Cotton Production Research Conference, Phoenix, Arizona, January 9-10, 1979

TN;

Biological Sciences Texas Tech University Post Office Box 4149 Lubbock, Ten 79409