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Effects of Green Manure Crops on Dryland Wheat Production in the Great Plains Area of Montana 全文
1959
Army, T. J. | Hide, J. C.
SynopsisGreen manure crops of sweetclover, field peas, and winter rye grown during part of the fallow period had no beneficial effects on dryland wheat yields, test weight, or protein content, There was no evidence that continued use of green manures materially affected soil nitrogen or carbon content.
显示更多 [+] 显示较少 [-]Bindweed (Convolvulus arvensis L.) Control and Seedling Emergence as Affected by Tillage, 2,4-D, and Competitive Crops 全文
1959
Wiese, Allen F. | Rea, H. E.
SynopsisBindweed on noncropped areas was controlled in 5 years with 2 annual applications of 2,4-D or by sweep tillage at 10 and 15 days after weed emergence. On winter wheat land bindweed was controlled with several combinations of sweep tillage and 2,4-D applications. Emergence of bindweed seedlings from the soil was reduced when application of 2,4-D was used exclusively for bindweed control.
显示更多 [+] 显示较少 [-]THE Annual cycle of limothrips cerealium haliday (thysanoptera) and its distribution in a wheat field 全文
1959
LEWIS, T.
Terrestrial and aerial populations of L. cerealium were studied simultaneously; ovarian dissections were made to detect different generations. The annual life cycle can be arbitrarily divided into six stages based primarily on the amount of flight activity: the females feed mainly on winter cereals and grasses in spring, many moving to later sown cereals in June and July, where most eggs are laid in the sheaths of the young leaves. First generation females leave cereals in August to feed on grasses before entering hibernation. Wheat ears with a water content of less than approx. 45% were not favoured by thrips. When winds blew consistently from the same quarter the initial infestation was greatest on the windward edge of the wheat crop.
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