Search

Rice blast is the most destructive disease to rice production globally. The objective of this review is to know the fundamentals of rice blast disease and to know the different methods for controlling blast disease. Rice blast disease has been recognised in more than 85 rice-producing countries worldwide. Currently, more than 100 R genes for blast resistance have been identified in rice. These resistance genes can be introgressed into a susceptible variety through marker-assisted backcrossing. Infested residues and seeds are the primary inoculum sources to spread the disease. Considering the importance of this disease, various management approaches have been practiced to control blast disease. The use of resistant varieties is an important measure to manage the disease. This review will provide use fulfacts about the pathogen and its epidemiology, assessment of resistance genes and effective control measure of rice blast disease through breeding and management. This update information will be helpful and guide to the research students and rice breeders to develop durable blast resistant rice varieties. So farmers will able to manage the blast disease in future. [ABSTRACT FROM AUTHOR]

A better water management is essential to obtain higher yield and increase irrigation use efficiency (IUE). We investigated the optimum fertigation requirement of chilli based on different crop evapotranspiration (ETc 100, 125, 150 and 200) and two different crop coefficients [single crop coefficient (single-Kc) and dual crop coefficient (dual-Kc)] in the tropical climate. According to the experimental results, chilli water requirement (ETc) using single-Kc and dual-Kc were 214 mm and 324 mm, respectively during the growing period. The results showed that total leaf area and dry weights of plant were significantly affected by different levels of fertigation and crop coefficients. Higher total leaf area was obtained from the higher level of fertigation and dual-Kc. Dry weights of plant (leaf, stem and root) decreased in lower levels of fertigation with single-Kc. However, no significant difference was observed by levels of fertigation and crop coefficient for root to shoot ratio. Significant differences for the interaction between different levels of fertigation and crop coefficients were found for photosynthetic rate (Pn), stomatal conductance (gs), transpiration rate (E) and relative chlorophyll content. Except maximum quantum yield of PSII (Fv/Fm), no significant difference was observed by interaction between different levels of fertigation and crop coefficients. The fresh fruit yield and IUE values in this study showed that there were significant differences for the interaction between different levels of fertigation and crop coefficients. The combination treatment 200ETc with dual-Kc enhanced Pn, gs and produced significantly higher fresh fruit yield. Thus, the findings of this study revealed that chilli grown in soilless culture could be fertigated with 200ETc using dual-Kc approach in tropical region for better plant growth, physiological activities and yield. © 2015 Friends Science Publishers [ABSTRACT FROM AUTHOR]

Seasonal drought stresses as a result of changes in global climate and local weather conditions are among the major factors adversely affecting growth and productivity of Robusta coffee (Coffea canephora pierre ex froehner) in many areas producing the crop. It is believed that there exists a wide range of genetic variability among Robusta coffee clones for traits associated with drought tolerance. Therefore, in an attempt to determine differences among Robusta coffee clones for some growth, physiological and biochemical parameters and identify drought-tolerant materials, 12 months old seedlings of six clones (IC-2, IC-3, IC-4, IC-6, IC-8 and R-4) were subjected to two treatments: well-watered control and drought-stressed (soil drying) by withholding irrigation for three weeks in a rain shelter at University Putra Malaysia, Malaysia. The rate of stress development, expressed as extent of wilting and damage to leaves, was considerably higher for clones IC-8, IC-4, R-4 and IC-2 than for IC-3 and IC-6 during the stress period. Leaf water potential (LWP), stomatal conductance (gs) and rate of net photosynthesis (PN) progressively decreased but leaf proline (LP) concentration substantially increased with time of exposure of the plants to soil drying. There was a considerable difference between coffee clones for the rate of change in these parameters. All the clones except IC-6 and IC-8 showed a negative carbon balance with the most negative value for R-4 at the end of the stress period. Six days after rewatering, LWP, gs and PN increased rapidly while LP concentration decreased and reached a level equivalent to those of well-watered plants, especially for clones IC-3 and IC-6. Among the drought-stressed plants, IC-6 and IC-3 had still significantly higher shoot growth, total dry matter yield and root to shoot ratio than did IC-2, IC-4, IC-8 and R-4. In general, clones IC-6 and IC-3 exhibited quite a better performance in almost all the parameters considered in this study and seemed to be less sensitive to drought stress. Hence, drought tolerance attributes in these clones could be linked to a more effective osmotic adjustment due to more rapid accumulation of LP and probably some morphological parameters, such as increased root-to-shoot ratio. However, further analyses at molecular level, detail biochemical studies and observations under diverse field conditions are required to come up with more conclusive recommendations. [ABSTRACT FROM AUTHOR]

The experiment was conducted to assess the responses of salinity on the growth, nutrient accumulation and yield of rice genotypes. Five Malaysian genotypes (MR33, MR52, MR211, MR232 and MR219), two salt sensitive (BRRI dhan 29 and IR20) and one salt tolerant genotypes (Pokkali) were evaluated in four levels of salinity. Two factors complete randomized design (CRD) was used with four replications. Dry weight of root, shoot and yield significantly decreased with the increase of salinity levels, while MR232 and MR211 were less affected. Na+ ions accumulations increased in the root and shoot with the increase of salinity, while the lowest accumulation was in MR211. Na+/ K+ratio sharply increased in the root with increasing the salinity. Whereas, Ca++/Na+ and Mg++/Ca++ ratio showed decreasing trend with increasing salinity level. The maximum amount of nitrogen and phosphorous accumulation was observed in the shoot of MR211, while Na+ in BRRI dhan29, K+ in Pokkali. The highest accumulation of Na+ and K+ observed in the root of MR219. The maximum Ca++ and Mg++ were found in MR33 and MR211, respectively. Considering all, genotypes MR211 andMR232 were found to be relatively tolerant to salt than the other genotypes. [ABSTRACT FROM AUTHOR]

The effect of biofertilizer and urea on growth parameters, yield and yield attributes of two mungbean varieties was investigated. Application of biofertilizer and urea was more effective in promoting plant growth and yield attributes than sole application of biofertilizer or urea. Among the fertilizer combinations, biofertilizer with recommended TSP, MP, gypsum and one-third urea exhibited superiority in plant height, number of branches plant-1, leaf area plant-1, number of nodules plant-1, chlorophyll content in leaves, total dry mass plant-1, absolute growth rate, number of pods plant-1, harvest index and seed yield as compared to other fertilizer treatments. Therefore, biofertilizer with 13 kg urea ha-1 may be recommended for increasing seed yield of mungbean. [ABSTRACT FROM AUTHOR]

Development of high yielding and stable varieties of lentil is a key researchable issue in Bangladesh. In this endeavour, 110 lentil accessions were evaluated during 2006-07 and 2007-08 cropping seasons at Ishurdi and Magura, two representative lentil growing areas in Bangladesh. The analysis of variance showed highly significant differences among genotypes, environments and genotype- environments, thus indicating substantial variability among genotypes for days to first flowering, days to maturity, number of pods per plant and seed yield per plot. Among four environments, Ishurdi 2006-07 was the most favorable and Magura 2006-07 was the least yielding. Biplot analysis provided information on wide and specific adaptation. Accessions ILL7656, ILL2532, N1M-134, 40-50134-5, ILL8605-2 and ILL2581 exhibited higher mean seed yield and performed stability across environments. Accession ILL5150 was the best performer for Ishurdi region and accession ILL4605 was the best performer for Magura region. Considering yield potential, early maturity and wider/specific adaptability, four accessions namely ILL5150, ILL2532, ILL7656 and ILL4605 were identified as the best performer and BLx98006-3 was the earliest. These precious accessions may serve as key donors as parents for use in breeding programmes to develop high yielding varieties or may be used directly as varieties for commercial cultivation in Bangladesh. [ABSTRACT FROM AUTHOR]

The experiment was conducted at the experimental field of Bangladesh Institute of Nuclear Agriculture, Mymensingh, Bangladesh from the month of March to May 2011 to investigate the effect of cultivars and seed rates on morpho-physiological characters, yield components and yield of summer mungbean [Vigna radiata (L.) Wilczek]. The experiment comprised three types of varieties viz., BINAmung-6 (bold seeded), BINAmung-7 (small seeded) and BINAmung-8 (medium seeded) and three seed rates viz., 30, 40 and 50 kg ha-1. The experiment was laid out in a two factor randomized complete block design with three replications. Number of branches plant-1, leaf area plant-1, total dry mass plant-1, relative growth rate, pod number plant-1, seed and biological yield plant-1 and harvest index decreased with increasing seed rate while reverse trend was observed in plant height and leaf area index. Results revealed that optimum seed rate of a mungbean variety depended on seed size. The variety having smaller size seeds require lower seed rate and vice versa. On an average over the varieties, the seed rate 40 kg ha-1 resulted in the highest seed yield in mungbean. The optimum seed rate for maximizing seed yield of bold seeded variety, BINAmung-6 was 50 kg ha-1. Similarly, the optimum seed rate for small seeded variety, BINAmung-7 and medium seeded variety, BINAmung-8 was 30 and 40 kg ha-1, respectively. The dry matter partitioning to economic yield was also higher at above optimum seed rates of the varieties. Among the varieties, BINAmung-8 produced the highest seed yield both per plant and per hectare due to its favourable dry matter partitioning to economic yield. [ABSTRACT FROM AUTHOR]

The banded leaf monkey (Presbytis femoralis femoralis) is the largest extant non-human primate in Singapore and its population is known to be critically endangered and restricted to the Central Catchment Nature Reserve. Prior to this study it was uncertain whether the species is reproducing in Singapore and there were confl icting reports about infant colouration, casting doubts on whether the subspecies in Singapore is different from that in Johor, Malaysia. Here we present the first report on reproduction, infant pelage colouration and development of the banded leaf monkeys in Singapore based on 22 months of observational data. We report at least six births from 2008 to 2010, and present evidence that there is at least one birth season in June/July for three consecutive years. Moreover several infants have survived beyond seven months, implying low infant mortality. The infants are born white, with a black line from head, along the spine, to tail that is intersected by a black line passing along the shoulders to the outer surfaces of both forearms thus forming a distinctive cruciform (cross-like) black pattern on the dorsum. This natal pelage pattern is consistent with that of the banded leaf monkey infants in Johor, suggesting no differentiation between the two populations based on infant colouration. These data are preliminary and more long-term research is needed to understand the reproductive behaviour of this native and elusive primate in Singapore. [ABSTRACT FROM AUTHOR]

Water stress occurring during the early phase of the reproductive growth stage may influence plant reproduction success. The objectives of this study were to evaluate the responses of pollen and seed yield components to water stress during anthesis in cultivated rice (Oryza saliva L.) varieties and weedy rice strains. Studies were conducted in 2007 using three cultivated rice varieties; MR 84, MR 219 and MR 232. In 2008 three weedy rice strains were obtained from Seberang Perak, Kuala Pilah and Tanjung Karang areas. Studies were conducted in the field where plants were grown in polybags and submerged in polyethylene tanks. Prior to anthesis, plants were subjected to water stress by taking the plants out of the polyethylene tanks for five days. Flag leaf relative water content (RWC) and relative injury (RI) were measured daily during the stressed period. Pollen production and pollen viability were measured upon re-watering. Seed yield components measured were grain number per panicle, 100-grain weight, percentage filled grain and percentage spikelet sterility at harvest. Water stress caused a 13 - 34% decline in the number of pollen grains per anther in cultivated varieties but increased pollen production in weedy strains. Percentage pollen viability declined by 40 - 45% in MR 219 and MR 232, but increased by 15% in MR 84 when plants were water-stressed. Percent pollen viability in weedy strains never exceeded 52% and significantly declined with water stress. For cultivated varieties, water stress increased total number of grain per panicle by 31%. In weedy strains, only Seberang Perak increased in the number of grain per panicle due to water stress. Spikelet sterility was relatively higher in cultivated varieties (16-50%) compared with weedy strains (10 - 23%). The 100-grain weight was not affected by water stress in both cultivated varieties and weedy strains. This study indicated that weedy rice strains would gain a competitive advantage by producing more filled grains when water deficit occurs during anthesis. [ABSTRACT FROM AUTHOR]

The influence of thermoplastic/bagasse fiber ratio, as well as electron beam irradiation on the physicomechanical properties of low-density polyethylene (LDPE) and high-density polyethylene (HDPE) composites has been investigated. The concentration of bagasse fibers ranges from 20 to 80 wt%. The results indicate that there is deterioration in the properties as fiber concentration increased; however, it becomes significant only beyond 50% (w/w) bagasse fibers in both LDPE and HDPE composites. Also, the data show that this decrease in the properties is more pronounced in HDPE rather than LDPE composites. It can be noticed that enhancing adhesion between fibers and thermoplastics can be achieved by irradiation of the thermoplastic phase prior to mixing at 10 up to 60 kGy; a maximum improvement in the properties is observed at 40 and 10 kGy for LDPE and HDPE, respectively. From the data it can be seen that the increase in the flexural properties is higher than 100%, while it does not exceed 65% for impact toughness. On the other hand, the reduction in water absorption is not more than 5.5%. Also, examining SEM micrographs reveals that there is some sort of adhesion between fibers and thermoplastics phases. [ABSTRACT FROM AUTHOR]

The article which examined the use of emulsion polymer for the preparation of bagasse fiber polymer-cement composites. It mentioned the irradiation of the pressed samples at various irradiation doses using electron beam (EB) accelerator. It found that the average value of hardness of irradiated composites were higher than those of unirradiated and control composites.

A pilot scale membrane plant was constructed and monitored in Shah Alam, Malaysia for municipal wastewater reclamation for industrial application purposes. The aim of this study was to verify its suitability under the local conditions and environmental constraints for secondary wastewater reclamation. Immersed-type crossflow microfiltration (IMF) was selected as the pretreatment step before reverse osmosis filtration. Secondary wastewater after chlorine contact tank was selected as feed water. The results indicated that the membrane system is capable of producing a filtrate meeting the requirements of both WHO drinking water standards and Malaysian Effluent Standard A. With the application of an automatic backwash process, IMF performed well in hydraulic performance with low fouling rate being achieved. The investigations showed also that chemical cleaning is still needed because of some irreversible fouling by microorganisms always remains. RO treatment with IMF pretreatment process was significantly applicable for wastewater reuse purposes and promised good hydraulic performance. [ABSTRACT FROM AUTHOR]

The influence of unsaturated polyester resin to sand ratios as well as γ-irradiation on the physico-mechanical properties of the sand-polyester composite has been investigated. The samples were prepared at different ratios ranging from 5% to 30% of unsaturated polyester to sand, then subjected to γ-irradiated between 10 and 100 kGy. The effect on the compressive strength, total porosity, and water absorption, in addition to infrared spectroscopy and thermogravimetric analysis (TGA) were studied. The results indicate that the compressive strength increases with the increase of unsaturated polyester resin and the γ-irradiated dose, whereas the total porosity and water absorption values were decreased. These are attributed to adhesion between the sand and unsaturated polyester under the effect of γ-irradiation. Infrared spectra showed the appearance of new bands as a result of the formation of the Si=C bond. Also, TGA showed that the thermal stability of the composite increases with the increase of exposure dose. [ABSTRACT FROM PUBLISHER]