Intergenotypic competition in mixed stands of spring wheat genotypes

Summary Grain yield and yield components were studied in the three spring wheat genotypes HD 2160 (dwarf), Kalyansona (semi-dwarf) and C 306 (tall) in pure stands as well as in their binary mixed stands during two years. The grain yields of the three genotypes in pure stands ranked as follows: HD 2160 > Kalyansona > C 306. Four mixed stands, 3:1 HD:K, 1:1 HD:C in the first year and 1:1 K:C, 1:3 K:C in the second year out-yielded the pure stand of the better component genotype by 4.4, 2.7, 3.3 and 0.8 percent, respectively. Out of the nine mixed stands four in the first year and seven in the second year out-yielded the midmonoculture yields and the increases ranged from 1 to 7.6 percent. Mixed stands were more stable than pure stands.The yield and yield components of the dwarf genotype HD 2160 scored less and those of the taller genotype C 306 scored higher in mixed stands. The semi-dwarf genotype Kalyansona yielded more with HD 2160 and less with C 306. Plant height but not high yielding ability conferred high competitive ability. With respect to competitive ability the three genotypes ranked as follows: C 306 > Kalyansona > HD 2160.The results illustrate the importance of intergenotypic competition in increasing crop production and reducing genotype-environment interactions. Such studies are important to agronomists as genotypes with high competitive ability can be useful to combat the weed problem. They are also important to plant breeders for predicting the fate of genotypes with low competitive ability in heterogeneous populations.     

Rice straw recycling: A sustainable approach for ensuring environmental quality and economic security

One of the major challenges in Asian countries is the effective management of rice straw. To ensure food security for their ever-growing population, Asian countries grow more rice, leading to increasing rice straw generation. Burning of rice straw, a common practice, is detrimental to both environmental and human health. However, if managed effectively, rice straw has the potential to safeguard the sustainability of agricultural ecosystems and to uplift the economic security of the population de...     

Influence of competition,irrigation levels and nitrogen fertilization on protein content and protein yield of three spring wheat (Triticum aestivum L.) cultivars

Protein content and protein yield of three spring wheat cultivars differing in morphological and physiological growth characters were found to be influenced by intercultivar competition, irrigation levels and nitrogen fertilization. The protein content of the tall cultivar C 306 and the protein yield of the dwarf cultivar HD 2160 were more than the other cultivars. Binary mixed stands were not superior to the better component cultivar. Intercultivar competition increased the protein content of dwarf and semi-dwarf cultivars, but decreased the protein content of tall cultivar. On the other hand, protein yield of the dwarf cultivar decreased and that of tall cultivar increased when grown in mixed stands. Protein yield of semi-dwarf cultivar increased when grown with dwarf cultivar, but decreased when grown with tall cultivar. Two or three irrigations increased the protein content and protein yield of all the three cultivars and their mixed stands over one irrigation. Protein content and protein yield of the cultivars and their mixed stands were higher when 150 kg N/ha was applied than when 80 kg N/ha was applied.     

Chungtaejeon,a Korean Fermented Tea,Scavenges Oxidation and Inhibits Cytokine Induced Proliferation and Migration of Human Aortic Smooth Muscle Cells

Oxidation susceptibility of serum lipid and the proliferation and migration of vascular smooth muscle cells (VSMC) from tunica media to the sub endothelial region are the key steps in the progression of atherosclerosis. The objective of this study was to determine the effects of Chungtaejeon (CTJ) on oxidation and cytokine induced proliferation and migration of human aortic smooth muscle cells (HASMC). The antioxidative effects of CTJ were evaluated by using 1,1-diphenyl-2-picryl hydrazyl (DPPH) scavenging assay, nitric oxide (NO) scavenging assay and thiobarbituric acid reactive substance (TBARS) assay. Similarly, the proliferation, migration and expression of matrix metalloproteinases (MMPs) in HASMC were assessed by MTT assay, transwell Boyden chamber assay and gelatin zymography, respectively. Western blotting was done to determine the protein expression of MMP-9, phospho extracellular regulated kinase (pERK1/2) and phospho c-Jun N-terminal kinase (pJNK). In results, the IC₅₀ values for DPPH and NO scavenging activities were 8.91 μg/ml and 14.32 μg/ml, respectively. Furthermore, CTJ inhibited TBARS formation dose dependently. The pretreatment of CTJ dose dependently inhibited the tumor necrosis factor-α (TNF-α) induced proliferation and MMP-9 expression and platelet derived growth factor (PDGF) induced migration of HASMC. Thus, CTJ can be suggested to have beneficial effect in the prevention of atherosclerosis.     

GENOTYPIC VARIATION FOR PRODUCTIVITY,ZINC UTILIZATION EFFICIENCIES,AND KERNEL QUALITY IN AROMATIC RICES UNDER LOW AVAILABLE ZINC CONDITIONS

Zinc (Zn) has emerged as the plant nutrient limiting rice growth in several parts of the world. About 50% of world soils are deficient in Zn and this is also true for India. An analysis of 0.233 million samples taken from different states showed that 47% of Indian soils are deficient in Zn. In India, Zn deficiency is widespread, especially in the rice–wheat cropping system belt of North India, which has high pH calcareous soils. Zinc is also now recognized as the fifth leading health risk factor is developing Asian countries, where rice is the staple food and Zn nutrition of humans and animals has recently received considerable attention. However, no reports are available on the effect of Zn fertilization on kernel quality of aromatic rices. The present study was therefore undertaken to study the effect of Zn fertilization on yield attributes, grain, and straw yield, Zn concentrations in grain and straw, Zn uptake, Zn use indices and kernel qualities of the aromatic rices. A field study at the Indian Agricultural Research Institute, New Delhi, India showed that Pusa Sugandh 4 (‘PS 4’) is a better than the earlier developed aromatic rice variety Pusa Basmati 1 (‘PB 1’) in terms of grain yield (4.08 tonnes ha^?1), kernel quality, zinc (Zn) concentrations in grain and Zn uptake (1,396.9 g ha^?1), recovery efficiency (5.2%), agronomic efficiency (122.7 kg grain increase kg^?1 Zn applied), partial factor productivity (1,064.7 kg grain kg^?1 Zn applied) and physiological efficiency (39,625 kg grain kg^?1 Zn uptake) of applied Zn. From the grain yield (4.64 tonnes ha^?1) viewpoint an application of 5 kg Zn ha^?1 was found sufficient for the aromatic rices grown on ustochrepts of north Indian rice-wheat cropping system belt. Application of 7.5 kg Zn ha^?1 increased Zn concentrations in the grain (37.0 mg kg^?1 DM) and straw (117.3 mg kg^?1 DM) of aromatic rices studied and this is important from the human and animal nutrition viewpoint under Indian conditions.     

Developing PGPR consortia using novel genera Providencia and Alcaligenes along with cyanobacteria for wheat

A pot experiment was undertaken using unsterile soil supplemented with the recommended dose of chemical fertilizers in order to investigate the effect of indole-3-acetic acid (IAA)-producing proteo- and cyanobacterial strains on the growth and yield of wheat (Triticum aestivum variety PBW343). Two proteobacterial (WRB4 Providencia sp. and WRB10 Alcaligenes sp.) and two cyanobacterial (WRC3 Anabaena oscillarioides and WRC4 Anabaena torulosa) strains were used individually and in combination. The treatment in which proteobacteriumWRB4 (Providencia sp.) was inoculated showed significantly higher values in comparison with controls for various plant-growth parameters recorded, i.e. shoot length, root length, shoot weight, root weight and crop biomass, followed by the treatment in which the WRC3 (Anabaena oscillarioides) was used. A positive interaction among the proteo- and cyanobacterial strains, in particular WRC3 and WRB4, was also observed by way of enhancement of plant-growth parameters. Significant enhancement in soil microbiological activities such as fluorescein diacetate (FDA) hydrolysis and dehydrogenase activity were recorded in the treatments, particularly in those inoculated with cyanobacterial strains, when compared with fertilizer controls. This is a first-time report on the potential of selected combinations of proteobacterial genera such as Providencia and Alcaligenes and cyanobacteria such as Anabaena as plant growth-promoting organisms in wheat crop.     

Carbofuran-induced biochemical changes in Clarias batrachus

The effect of carbofuran, an organo-carbamate pesticide, upon the level of protein as well as the activity of lactate dehydrogenase (EC 1.1.1.28, LDH) was studied by exposing the teleost fish, Clarias batrachus, to different subacute con-centrations (0·01 and 0·02 mg litre^-1) for 96 h and 15 days. The results showed a drastic decrease in the protein content in different body organs of the fish. The pesticide also caused a significant decrease in the level of activity of LDH in different body tissues of the fish, the effect being more pronounced in the gills, muscle, brain and liver than in kidney and heart. The decrease in protein content and the activity of LDH in fish tissues was more marked at the higher concentration of the pesticide for the longer duration of treatment. The results suggested that carbofuran has an effect at very low concentration (compared to its LC₅₀ value) possibly at the level of protein metabolism, and also inhibits the activity of LDH, the terminal glycolytic enzyme. © 1998 SCI     

The influence of nitrification inhibitors and slow release nitrogen materials on transformations of fertilizer nitrogen in soils of fluctuating moisture content

A laboratory study was made of nitrogen transformations in a sandy clay loam given either urea with and without nitrification inhibitors or slow-release nitrogen fertilizers. Moisture conditions were field capacity, continuous flooding, and alternate flooding and drying. Urea nitrogen was mineralized and fairly well conserved in soil either at field capacity or under continous flooding, but was rapidly lost under alternate flooding and drying. Denitrification losses were reduced with nitrification inhibitors. Oxamide, isobutylidene diurea, and sulfur-coated urea were as effective as the inhibitors in reducing losses under alternate flooding and drying.     

Cancer chemopreventive and antioxidant activities of pterostilbene,a naturally occurring analogue of resveratrol

Pterostilbene, a natural methoxylated analogue of resveratrol, was evaluated for antioxidative potential. The peroxyl-radical scavenging activity of pterostilbene was the same as that of resveratrol, having total reactive antioxidant potentials of 237 +/- 58 and 253 +/- 53 microM, respectively. Both compounds were found to be more effective than Trolox as free radical scavengers. Using a plant system, pterostilbene also was shown to be as effective as resveratrol in inhibiting electrolyte leakage caused by herbicide-induced oxidative damage, and both compounds had the same activity as alpha-tocopherol. Pterostilbene showed moderate inhibition (IC50 = 19.8 microM) of cyclooxygenase (COX)-1, and was weakly active (IC50 = 83.9 microM) against COX-2, whereas resveratrol strongly inhibited both isoforms of the enzyme with IC50 values of approximately 1 microM. Using a mouse mammary organ culture model, carcinogen-induced preneoplastic lesions were, similarly to resveratrol, significantly inhibited by pterostilbene (ED50 = 4.8 microM), suggesting antioxidant activity plays an important role in this process.     

Efficiency of Urea,Nitrification Inhibitor treated Urea and Slow Release Nitrogen Fertilizers for Sugarcane

A field experiment conducted for two crop seasons (1976-77 and 1977-78) showed that the treatment of urea with nitrification inhibitor Nitrapyrin (also refered as ‘N-Serve’) or neem (Azadirachta indica A. Juss) cake increased its efficiency by preventing N losses and produced significantly more cane. In one of the years sulphur coated urea (Gold N) at lower rate (75 kg N/ha) gave higher sucrose content in juice and significantly more commercial cane sugar (CCS) than uncoated urea. Considering both the cane yield and CCS production mixing or coating of urea with neem cake holds considerable promise and needs wider testing along with and in comparison to nitrification inhibitors and sulphur coated urea and other slow release fertilizers for increasing the efficiency of nitrogen applied to sugarcane.