Crop yields, increasing soybeans

In the southern part of Taiwan, a crop of rice is often followed immediately by a legume crop. Yields of soybeans have been increased by several hundred kilograms per hectare by burning the rice straw prior to planting the soybeans. Rice (46) hypothesized that the decreased... 

In the United States, DDT was used extensively in homes as well as on crops, such as cotton and soybeans. Because of its stable chemical structure, DDT did not break down quickly in the environment, which meant that it did not have to be applied as often. At first, everyone was pleased with DDT as crop yields increased and diseases such as malaria and typhus were controlled. 

In the 1930 s, crop yields in the United States, England, India, and Argentina were essentially the same. Since that time, researchers, scientists, and a host of federal policies in each country have helped farmers dramatically increase yields of corn, wheat, soybeans, cotton, and most other major commodities. Today, fewer farmers feed more people than ever before. This success, however, has not come without costs. 

Up to that point, safflower seed production had been on a continued upward spiral in the United States, which carried through to 1963. Safflower oil had been price competitive with soybean oil, particularly in the western United States and Japan, since soybean oil produced in the Midwest was at a freight disadvantage. The introduction into California of new varieties of wheat developed by the Borlaug program in Mexico allowed California farmers to achieve increasingly better wheat yields. In the 1950s, safflower was easily able to compete with wheat or barley as a rotation crop for California s rice or cotton farmers, but once wheat yields increased and safflower yields remained constant, safflower seed prices (and consequently oil prices) were forced to rise to compete for the farmer s favor. 

Applications of Mo did not increase crop yields from acid soils in Brazil limed to pH > 6.0 (Franco and Day, 1980). Likewise, Boswell (1980) found that Mo application did not increase soybean yields from soils limed to values above pH 6.2. 

Depolymerized chitin, carboxymethyl, and hydroxyethyl-chitin were used to coat soybean seeds before plantation in the field. It was reported that dry weight of the plants increased by 8% and the crop yield also increased by 12% in comparison to the control (Hirano 1996). Potato tubes were also coated with chitin and chitosan powder and the yield of potato increased up to 50% (Hirano 1996). Wheat seeds were also coated with chitosan and vigor index of wheat seedlings increased by 20%-30% compared to the control, and suitable concentration for chitosan treatment was 4 mg/mL (Reddy et al. 1999). 

Effects of chitosan application on the growth and yield of some crops such as soybean, upland rice, mini-tomato, lettuce, and radish were carried out by mixing chitosan 100 kDa at 0.1%-0.5% of soil. It was found to be strongly effective to the growth of the plants. Chitosan application at concentration of 0.5% was suitable for soybean and upland rice, but 0.1% was more effective on lettuce and mini-tomato. The leaf area of lettuce increased by 50%-60% compared to the control after three times of foliar application at concentration of 0.1% and the leaf area of radish also increased up to 100% at concentration of 0.5% (Chibu 2001). 

Vernonia" seeds contain about 42% of oil in contrast to soybean seeds, which contain only 17% oil. The maximum seed yield reached at this development stage of Vernonia galamensis is 2227 pounds per acre. Unfortunately, it has not been reproduced. Increased yield of vernonia oil, however, is expected by breeding as greater genetic diversity becomes available and by better management of the crop. The best soybean seed yield is 1926 pounds per acre (1979), which was the best soybean oil year... 

The effect of zearalenone on crop development may be connected to its influence on the status and functioning of the photosynthetic apparatus (Koscielniak et al. 2008). The after-effects of zearalenone on the growth of soybean and wheat plants, net photosynthesis and transpiration rates, stomatal conductance, photochemical efficiency of photosystem 2 and on final seeds yield were determined. Modifications in leaf area were more pronounced in soybean than in wheat, and this tendency increases in successive developmental phases. The net photosynthesis was stimulated during the juvenile phase and during that of the final one by about 13.6% (average) in soybean plants. Stimulation of transpiration was also observed after... 

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