Pregerminated seeds were grown in nutrient solution containing 30 ppm Al and normal nutrient solution and relative root length, relative shoot length, relative root weight, and relative shoot weight were determined at 14 day old seedling stage. Relative root length was more pronounced than the other three parameters for detecting the degree of tolerance. Of 62 varieties tested, 11 varieties namely Siyam Kuning, Gudabang Putih, Siyam, Lerno, Khao Daeng, Siyamhalus, Bjin 12, Kitan, Seribu Gantang, Bayar Raden Rati, and Padi Kanji were found more tolerant than the improved tolerant variety IRAT 104. Tolerant varieties Azucena, IRAT 104, and Moroberekan and sensitive varieties, IR45 and IR1552, were studied in detail and were used along with two other varieties to investigate the genetics of tolerance to aluminum toxicity by diallel analysis of relative root length. The diallel analysis showed the predominance of additive gene action along with the significance of other components. Graphical analysis of variance and covariance showed that IR45, IR29, and IR1552 had an excess of recessive alleles and Moroberekan, IR43, Azucena, and IRAT 104 with more dominant alleles for aluminum toxicity tolerance. The graphical analysis further indicated the partial dominance of the trait and the absence of epistasis. The high narrow sense heritability value obtained (0.82) suggested that pedigree method of breeding would be a suitable breeding strategy to develop cultivars tolerant to aluminum toxicity

The varieties included in the State register and prospective breeding samples were assessed on protein, oil and some other nutrient substances content with the purpose of finding out the best soybean varieties for industrial seed processing into food products. Crude protein content in soybeans of the varieties Arkadia Odeska, Kyivska-27, Kyivska-91, Veselka, K-995, K-451, K-387 reached 50. The highest protein content (43-46) was revealed in Kyivska-91, Arkadia Odeska, K-995, K-451. Nyva, Veselka, Yug-40, Kirovogradska-5, K-730, K-451 were distinguished by lipid content (up to 22,85). It is found out that the varieties Kyivska-91 and K-451 had high both protein and lipid content.

Rice (Oryza sativa L.) straws of four varieties and strains (Akichikara, Koshihikari, Hokuriku 147 and Hokuriku 148) were compared on nutritive value. In order to investigate the digestibility and energy balance of rice straw, four Japanese native goats were fed rice straw at maintenance TDN level by using a Latin square design. Rice straws were adjusted with soybean meal so that crude protein content was 12%. Culm length (cm) and straw yield (DM kg/a) in Koshihikari were higher than those in other varieties. There was no apparent difference among the varieties and strains in chemical composition. However, acid detergent lignin content tended to be lower in Hokuriku 147. Digestibility of dry matter, organic matter, ether extract, organic cell wall, acid detergent fiber, cellulose and energy of Hokuriku 147 were higher than the other varieties. Total digestible nutrient, digestible energy and metabolic energy in Hokuriku 147 were higher than those in Akichikara and Koshihikari. Energy excretion in feces and urine was lower in Hokuriku 147 than those in Akichikara and Koshihikari. It is suggested that differences in nutritive value of rice straw are mainly dependent on digestibility of fiber ingredient and energy excretion in feces and urine

Experiment was designed to compare a local substrate (fine loose coconut fibre) with two import synthetic substrates (Rockwool and Polyurethane) and their effects on growth, yield and some characteristic qualities of two cantaloupe varieties. The drippers were supplied and recirculated with nutrient feed to plants automatically controlled for pH and electro conductivity (EC.). Much attention was paid to the changes of nutrient solution in the substrate slabs which were daily monitored by manual pH and EC maters. A review on hydroponics in Thailand, an installation of automatic system and the composition and management of nutrient solution were also given. The results showed that the local compostable substrate met the present economic, ecological and ergonomic standards of Thai greenhouse horticulture. The relative merit of one substrate to another were drawn from this trial. Recommendation that should be made was that the growing techniques should be adjusted to the properties of each type of substrates. Besides, the problems occurred during the experiment were identified.

Sweetpotato is extensively used as animal feed around the world. To increse its demand will depend on how competitive it is in relation to other plants in the supply of available nutrients to animals. In this context, sweetpotato breeding should consider dry matter production and available nutrient content (energy and protein). The structure of starch, trypsin inhibitors, and fiber change nutrient availability, and this is affected by processing (heat treatment) and the animal being fed (ruminant versus monogastric). Collaborative research between the National Agrarian University and CIP has begun to determine the potential of prevalent sweetpotato varieties as feed for poultry and dairy cattle in relation to users' demand. Possible constraints will be identified, and these could require breeding for improvement. Other aspects to consider are the potential for sweetpotato in marginal areas for feed and for increasing the sustainability of agricultural systems.

Seeding nitrogen-fixing species is a proven silviculturnl practice to increase site nutrient capital, but species' responses are site specific. Alsike closer (Trifolium hybridum L.), white clover (T. repens L.), black medic (Medicago lupulina L.), cicer milkvetch (Astragalus cicer L.), two varieties of birdsfoot trefoil (Lotus corniculatus L.), and Hederma pine lupine (Lupinus albicaulis Dougl.) were planted at several elevations on the Wenatchee National Forest in Washington state. After 2 years, alsike clover and Hederma pine lupine were the most successful species on high-elevation (>1,219-m or 4,000-ft) sites, and black medic and Hederma pine lupine were the best performers on low-elevation sites. Average total nitrogen inputs from top growth of planted species during the 1991 growing season were between 20 and 115 kg/ha (18 and 103 lb/acre). Nitrogen delivered by atmospheric fixation was between 6 and 40 kg/ha (5 and 36 lb/acre). Legumes can successfully establish in eastern Washington, ameliorating losses in nutrients after logging and residue treatment. Legumes increased total nitrogen on these sites and enhanced nutrient cycling in planted areas.

Seeding nitrogen-fixing species is a proven silviculturnl practice to increase site nutrient capital, but species' responses are site specific. Alsike closer (Trifolium hybridum L.), white clover (T. repens L.), black medic (Medicago lupulina L.), cicer milkvetch (Astragalus cicer L.), two varieties of birdsfoot trefoil (Lotus corniculatus L.), and Hederma pine lupine (Lupinus albicaulis Dougl.) were planted at several elevations on the Wenatchee National Forest in Washington state. After 2 years, alsike clover and Hederma pine lupine were the most successful species on high-elevation (>1,219-m or 4,000-ft) sites, and black medic and Hederma pine lupine were the best performers on low-elevation sites. Average total nitrogen inputs from top growth of planted species during the 1991 growing season were between 20 and 115 kg/ha (18 and 103 lb/acre). Nitrogen delivered by atmospheric fixation was between 6 and 40 kg/ha (5 and 36 lb/acre). Legumes can successfully establish in eastern Washington, ameliorating losses in nutrients after logging and residue treatment. Legumes increased total nitrogen on these sites and enhanced nutrient cycling in planted areas.

The response of three varieties of gerbera plants, Gerbera jamesonii cvs. Fame, Rosabella and Sunspot cultivated in bags and grown on three substrates, perlite, peat:perlite 1:1 and pumice, was studied in the Mediterranean Agronomic Institute of Chania in Crete. The purpose was to investigate the performance and suitability of these substrates for soilless culture, their effect on plant growth, yield and quality of flower production, as well as the effect of irrigation treatment, water and nutrient supply along the growing cycle. The effect on photosynthetic rate Pn, stomatal conductance gs, vapour pressure deficit VPD, leaf transpiration E, leaf water potential, soil water potential and crop coefficient K=ETa?To were studied.

Cassava sweet potato intercropping experiments were carried out at Ukiriguru (semiarid zone), Tanzania during the period from 1989-91. Four cassava varieties used were, Msitu Zanzibar, Alpim valenca, Mzimbirala and Liongo control. The second experiment tested four cassava planting densities, 6666, 10000, 13333 and 20000 plants per hectare. In the two trials, cassava was planted with single or double rows of sweet potato on the same ridge. Basal dressing of inorganic fertilizers at the rate of 60 N, 30 P, and 30 K kg/ha was applied to one half while other half was left unfertilized. Results showed that cassava and sweet potato can be successfully and profitably intercropped since they have different growth durations that allowed for yield gains through better utilization of space and time. A sound fertilization practice in cassava/ sweet potato associations was deemed necessary to ensure soil fertility maintenance. Although nutrient use was a limiting factor for increased productivity, other potential agronomic practices such as the use of organic matter, crop residues, farmyard manure and integration of leguminous crops, to improve soil texture and nutrients may be additional attractive options for farmers. Some of the other aspects that need more research are, adjusting cutting length of cassava to avoid early shading of the intercrop, better rooting cultivar use, and type of seedbed used for sweet potato cuttings. Further studies are also warranted to know specific nutrient requirements in this intercrop and critical nutrient demand times of the individual crops in this association.

The effects of three doses of lime (0, 500 an 1500 kg/ha) on total root yields, nutrient content on leaves and other production variables, were evaluated in two cultivars of manioc (Tempranita and M-VEN-180). The experimental design used was the random block with arrangement in divided parcels and three replicates. The final results did not show significant differences in root yields when comparing different dose of lime and in the interaction lime versus varieties. Only a significant effect of the variety factor in root yield was found, response the M-VEN-180 cultivar having better response. This indicates that the cultivars respond in independent ways to different doses of lime. The differences obtained were due to its genetic potential.