Investigations were conducted in 1988-1989 in Timiryazev Agricultural Academy. Productivity of early ripening onion variety Vesta and mid-ripening leek strain sample TSKhA-T was investigated; it was studied on soddy-podzolic medium-textured loams with sowing density 180 and 350 thousand plants per ha and different backgrounds of mineral nutrition: without fertilizers; with applying 90N60P90K, 180N80P120K entirely and in rows. The varieties studied varied in the amount and intensiveness of absorbing the main nutrient elements, their removal and consumption, varying in its turn, with density of planting rate and way of applying fertilizers. The efficiency of using nutrient elements from fertilizers by leek greatly depended on conditions of moistening. Data on removal of nutrient elements - N - 276; P2O5 - 45 and K2O - 195 kg/ha - may be used as normative for leek culture. Optimum variants of the experiment may be recommended for production.

Investigations were conducted in 1988-1989 in Timiryazev Agricultural Academy. Productivity of early ripening onion variety Vesta and mid-ripening leek strain sample TSKhA-T was investigated; it was studied on soddy-podzolic medium-textured loams with sowing density 180 and 350 thousand plants per ha and different backgrounds of mineral nutrition: without fertilizers; with applying 90N60P90K, 180N80P120K entirely and in rows. The varieties studied varied in the amount and intensiveness of absorbing the main nutrient elements, their removal and consumption, varying in its turn, with density of planting rate and way of applying fertilizers. The efficiency of using nutrient elements from fertilizers by leek greatly depended on conditions of moistening. Data on removal of nutrient elements - N - 276; P2O5 - 45 and K2O - 195 kg/ha - may be used as normative for leek culture. Optimum variants of the experiment may be recommended for production

Die Zufuhr der Naehrstoffmengen muss die langfristige Erhaltung der Naehrstoffvorraete im Boden und die Schonung des Grundwassers beruecksichtigen. Dies erfordert eine konsequente Bilanzierung aller Naehrstoffe. Unausgewogene Bilanzen fuehren frueher oder spaeter zu Problemen bei Bodenfruchtbarkeit und Grundwasser

Due to the acidifiation of the soils the issue of aluminium toxicity will be more and more emphasized. A part of the varieties grown in Hungary possesses, however, a certain degree of tolerance, but it deemes to be advisable to increase this tolerance and to widen the group of tolerant genotypes. This may be achieved in the simpliest way by applying haploid mutant selection methods. But in order to develop an effective method, it is indispensable to know how the aluminium and low pH given to the induction nutrient medium would influence the anther induction and the fertile green plant regeneration. Based on the authors' results, the aluminium toxicity can be well simulated also in anther culture, the 5 micro M1 solution of Al3+ applied to the nutrient medium with low pH (pH: 4.2 and 4.5) reduces considerably the callus induction. The higher concentrations of AL3+ destroy entirely the microspore population. On regeneralion nutrient medium 190-2 with normal pH, the calluses originating from induction nutrient medium containing aluminium may be regenerated by adequate frequency. According to the seedling test results of grains originating from fertile dihaploid plants, an increase may be expected in the variability of aluminium tolerance even if the aluminium treatment is applied only in the induction phase. The multiplication of progenies and the testing of their aluminium tolerance are now going on

To determine the effect of silica in rice plants on survival of the brown planthopper [BPH] (Nilaparvata lugens Stal.), five rice varieties (TN1, IR22, IR46, IR72 and Mudgo) were grown in nutrient solution having different concentrations of silica (0, 100, 200, 300, and 400 ppm). The experiment was in split plot design with four replications. Ten 1-day old first instar BPH nymphs were confined (in a mylar cage) on a plant (45 days old) receiving one of the silica treatments. The BPH population growth indexes were significantly higher on rice grown without silica than on those provided with silica. However, at the "0" level of silica, the population growth indices were not significantly different among BPH-resistant (IR72 Mudgo), moderately resistant (IR46) and susceptible (TN1, IR22) rice varieties. The results indicate that the level of silica in the soil and ability of the rice genotype to absorb the element may determine the level of resistance to BPH

Variability in millet stands in West Africa is clearly visible as early as three weeks after planting. The objectives of this study were to determine the influence of pH and chemical toxicities on millet germination and seedling growth and to compare varietal tolerance of toxic conditions. A nutrient solution study was carried out with a series of Hoagland-based nutrient solutions. Germination percentage was calculated, and root and shoot lengths were measured for one week. Critical values were determined for toxic elements. The only treatment which reduced germination percentage significantly was copper (Cu) concentrations >0.05M. Solution pH values between 5 and 7 resulted in the best root growth, though shoot growth was unaffected by pH. The roots were more sensitive than the shoots to several [aluminum (Al), boron (B), zinc (Zn)] of the elemental toxicities studied. Soil Al and manganese (Mn) levels may be high enough to have toxic effects on millet roots. However, natural soil iron (Fe), Cu, and Zn levels were much lower than the critical levels determined in the nutrient solution study. The improved varieties were more tolerant of Fe and Zn toxicity than the LOCAL variety, but the LOCAL variety was more tolerant of high B concentrations.

Variability in millet stands in West Africa is clearly visible as early as three weeks after planting. The objectives of this study were to determine the influence of pH and chemical toxicities on millet germination and seedling growth and to compare varietal tolerance of toxic conditions. A nutrient solution study was carried out with a series of Hoagland-based nutrient solutions. Germination percentage was calculated, and root and shoot lengths were measured for one week. Critical values were determined for toxic elements. The only treatment which reduced germination percentage significantly was copper (Cu) concentrations >0.05M. Solution pH values between 5 and 7 resulted in the best root growth, though shoot growth was unaffected by pH. The roots were more sensitive than the shoots to several [aluminum (Al), boron (B), zinc (Zn)] of the elemental toxicities studied. Soil Al and manganese (Mn) levels may be high enough to have toxic effects on millet roots. However, natural soil iron (Fe), Cu, and Zn levels were much lower than the critical levels determined in the nutrient solution study. The improved varieties were more tolerant of Fe and Zn toxicity than the LOCAL variety, but the LOCAL variety was more tolerant of high B concentrations.

Four varieties of dry beans (Phaseolus vulgaris) grown in four different areas of Burundi were analyzed for moisture, protein, fat, ash, mineral (potassium, calcium, magnesium, iron, copper, zinc, and phosphorus), essential amino acids (isoleucine, leucine, lysine, methionine, phenylalanine, threonine, valine) and antinutritional factors (raffinose oligosaccharide, trypsin inhibitor, hemagglutinin, tannin and phytic acid) contents. In-vitro digestibility of dry bean proteins was also evaluated. The concentrations observed for the proximate composition. protein quality, and antinutritional factors varied significantly (P < 0.05) among the 13 'variety-locality' combinations investigated in this study. Mean values for moisture, protein, fat, ash, and carbohydrate were 9.19%, 22.26%, 1.01%, 4.47%, and 72.33% respectively. They were 525, 55.2, 38.2, 7.63, 0.92, 7.33 and 456 mg/100 g for potassium, calcium, magnesium, iron, copper, zinc and phosphorus, respectively; and 7.35, 14.49, 13.49, 1.59, 9.85, 9.08 and 9.11 mg/g for isoleucine, leucine, lysine, methionine, phenylalanine, threonine and valine, respectively. Finally values for raffinose, stachyose, trypsin inhibitor, hemagglutinin, tannin and phytic acid were respectively 2.20 mg/g, 18.40 mg/g, 15.02 TUI X 10-3/g, 2.15 HU X 10-3/mg, 14.99 mg catechin equivalent/g and 16.50 mg/g. The levels obtained for different nutrients (except for some minerals) and antinutrients were in agreement with those found in dry beans in other areas of the world. Protein digestibility ranged from 67.47% (Calima variety from Kirimiro) to 71.99% (A410 variety from Imbo). These values were comparable to those obtained in other countries. Statistical analyses of data confirmed that nutrient content, protein digestibility and undesirable factors were influenced by both variety and locality. Relationships between some dry bean nutrients and between antinutritional factors and protein digestibility were also observed.