Productivity of high-yielding crops

Abstract

By using good varieties (lines) and by applying coating urea which releases nitrogen slowly, extremely high yields were obtained in several crops. Based on the high yields and appropriate fertilizer application, it was difficult to consider in this experiment that deficiency or excess of nutrient elements (minerals) occurred in plant, so that the mineral status of crops could be adopted as criterion for high yield. The results obtained were as follows.1) Amount of minerals absorbed was calculated by the following equation: Ym=Ym/YbxYb=MRI• where Yb is the biological yield, Ym is the mineral yield (amount of minerals absorbed), MRI is the mineral requirement index. The MRI did not show any significant difference between the "high yield" and "standard yield" treatments in each crop with a few exceptions, indicating that the Yb is the main factor which determines the Ym in each crop.2) The MRI differed clearly among crops in the "high yield" treatment. MRI(N) was higher in soybean and winter wheat than in rice, maize, and potato. The MRI(P) was high in soybean, low in winter wheat and maize. The MRI(K) values were almost identical among the crops except for the "standard yield" treatment in winter wheat and maize. The MRI(Ca) and the MRI(Mg) were high in only soybean.3) For the "high yield" treatment, the Ym(N), the Ym(Ca), and the Ym(Mg) were high in winter wheat, and soybean, the Ym(P) was high in soybean, the Ym(K) was high in winter wheat, maize, and potato.4) The HI(DM) was 46% in soybean, 92% in potato, and 47-59% in gramineous plants, but the HI(N), the HI(P), and the HI(K) were higher in soybean and potato than in gramineous plants. Thus, harvesting organs required carbohydrate, N, P, and K intensively in potato, but only N, P, and K intensively in soybean.Key Words: harvest index of mineral, high yield, mineral requirement index.Abbreviations: Yb, biological yield (dry weight of whole plant without roots); Ye, economic yield (dry weight of harvesting organs, e.g. grains or tubers); Ym, amount of mineral absorbed (mineral yield), Ym(N), Ym(P), Ym(K), Ym(Ca), and Ym(Mg), Ym of N, P, K, Ca, and Mg, respectively; MRI, mineral requirement index; MRI(N), MRI(P), MRI(K), MRI(Ca), and MRI(Mg), MRI of N, P, K, Ca, and Mg, respectively; HI, harvest index; HI(DM), HI(N), HI(P), HI(K), HI(Ca), and HI(Mg), HI of dry matter, N, P, K, Ca, and Mg, respectively. 446M. OSAKI et al.As the productivity (Tanaka and Osaki 1983) and content of nutrient elements (minerals) in each organ (Tanaka 1985) depend on the kind of crops and the conditions of cultivation, the accumulation of minerals, distribution to each organ, and balance among each mineral also vary with each crop and methods of cultivation.In a previous paper (Osaki et al. 1991), the productivity of the "high yield" crops, which gave yields about 1.5 to 2 times higher than those of the "standard yield" crops, was reported. Namely, "high yield" crops were cultivated by the application of slow release coating urea and a slightly high planting density using high-yielding ...

Yield and Nutrient Uptake of Soybean Cultivars Under Intensive Cropping Systems

“…All overall average macronutrient uptake values were similar to those of previous reports (Table 8). N uptake was higher than the previously reported values of between 70 kg ton-1 (Osaki, 1991) and 83 kg t -1 (EMBRAPA 2011), indicating higher N demand by current cultivars. The P uptake (11.1 kg t -1 ) was similar to that reported by Osaki (1991;11.7 kg t -1 ) and lower than that reported by EMBRAPA (2011; 15.4 kg t -1 ).…”

“…The studies of Bataglia et al (1976), Osaki (1991), and Tanaka et al (1993) investigated nutrient uptake by soybeans in Brazil and were used as references for several fertilization and liming recommendation guidelines in Brazil. However, soybean cultivars have improved since their publications and now soybean cultivars have increased yields, shortened crop cycles and growth habits to allow cropping systems with corn as second harvest.…”

Effect of Potassium Nutrition on Current Photosynthesized Carbon Distribution to Carbon and Nitrogen Compounds Among Rice, Soybean, and Sunflower

“…In that study, the amount of dry matter of the cereal (wheat) and legume (soybean) crops in the potassium-deficient field was 85-87% that in the control field, while the amount of dry matter of the root crops (potato and sweet potato) was less than 50% that in control field. [3,4] The dry matter of the sunflower was also affected severely by the potassium deficiency, as reported in the current paper. Therefore, we classified sunflower as a type II crop.…”

“…[8] The amount of dry matter in type I crops, including cereals (wheat) and legumes (soybean), in the K-deficient field was 85-87% that in the control field, while the amount of dry matter in the root crops (type II; potatoes and sweet potatoes) was less than 50% of that in the control field. [4,15] Consequently, it is clear that a low potassium concentration in the soil causes plant growth to decrease severely in type II crop, but has only a slight effect on type I crops.…”

“…Sunflower is not root crops, however since the top=root ratio remained constant in sunflower during growth, photosynthates were distributed more to the roots in sunflower than in cereal crops. [4] Also, since the Kc-Nc relationship in sunflower was typical of type II crop (Fig. 1), it was concluded that sunflower had root crops-like characteristics.…”