Study of fertility restoration and genetic diversity of drought-tolerant breeding lines for hybrid rice (Oryza sativa L.) development

Journal of Crop Science and Biotechnology - The identification of fertility restoration and genetic diversity of drought-tolerant breeding lines will be useful for the development of promising...     

Identification of ‘Ca. Phytoplasma asteris’, banana bunchy top virus and banana streak MY virus associated with Champa and Sabri banana cultivars in Tripura,a North Eastern state of India

European Journal of Plant Pathology - Symptoms of bunchy top, little leaf, leaf chlorosis with chlorotic streaks, leaf necrosis and stunted growth were noticed in two banana cultivars, Champa and...     

Non-destructive estimation of chlorophyll and nitrogen content in leaf of Rosa damascena (Mill)

Chlorophyll (Chl) and nitrogen (N) status of leaves provide valuable information about the physiological condition of plants. The conventional methods for measuring Chl and N contents in leaves are destructive, costly, time-consuming, and do not allow repetitive measurement of the same sample. The Damask Rose (Rosa damascena Mill) is an important aromatic crop in the western Himalaya region in India. Generally, flower yield and oil yield of the Damask rose are correlated with nitrogen, phosphorus, and potassium (NPK) levels in the leaf at the bud development stage. The dynamics of N within the rose plant have not been reported clearly. Thus, there is a pressing need for non-destructive techniques to estimate Chl and N content in the leaf of the Damask rose. Our objective was to establish an appropriate mathematical relationship between the Chl content index (CCI) value and the total Chl/N contents for non-destructive estimation of total Chl and N in the leaf of the Damask rose. The regression models were developed with destructively measured parameters (total Chl and N) as the dependent variable and a parameter derived from CCM-200 as the independent variable (CCI). We found that polynomial regression models are suitable for non-destructive estimation of total Chl, and the model predicted values were very close to traditionally measured values with a root mean square prediction error (RMSEp) less than 0.20?mg?g^?1 of Chl. In the case of N estimation, a power regression model was appropriate with lowest Akaike's information criteria (AIC) and root mean square validated error (RMSEv) value. Significant correlations (P?≤?0.001) were observed between traditionally measured values and our model predicted values in both cases.     

Timber species grouping in Bangladesh: linking wood properties

Timber species grouping (TSG) is essential for meaningful and cost-optimal use of wood. Bangladesh forests are exceedingly diverse and comprise many woody species which are potentially suitable for versatile uses including structural materials. Traditionally, widely known tree species are used for structural timber because technological properties of most of the species are poorly known. In this study, a hierarchical agglomerative cluster analysis based on three selected wood properties [i.e., wood density, modulus of elasticity (MOE) and modulus of rupture (MOR)] of seventy-nine timber species was done. The clustering process led to the formation of four distinct species groups [i.e., very low (TSG1), low (TSG2), medium (TSG3) and high (TSG4)]. However, the species grouping patterns also varied from trait to trait. This might be due to moderate relationship between density and MOE (r ² = 0.46) or MOR (r ² = 0.52). Species of the TSG1 group are mainly characterized by extremely low trait values, while the TSG4 group consists of species having exceedingly high trait values. The TSG2 and TSG3 groups are characterized by low and medium trait values. Hence, it is suggested to select suitable species from these groups, particularly the lesser known high-quality species in afforestation and reforestation programs to meet future timber demand in Bangladesh.     

Aquaculture and stress management: a review of probiotic intervention

To meet the ever‐increasing demand for animal protein, aquaculture continuously requires new techniques to increase the production yield. However, with every step towards intensification of aquaculture practices, there is an increase in stress level on the animal as well as on the environment. Feeding practices in aqua farming usually plays an important role, and the addition of various additives to a balanced feed formula to achieve better growth is a common practice among the fish and shrimp culturists. Probiotics, also known as ‘bio‐friendly agents’, such as LAB (Lactobacillus), yeasts and Bacillus sp., can be introduced into the culture environment to control and compete with pathogenic bacteria as well as to promote the growth of the cultured organisms. In addition, probiotics are non‐pathogenic and non‐toxic micro‐organisms, having no undesirable side effects when administered to aquatic organisms. Probiotics are also known to play an important role in developing innate immunity among the fishes, and hence help them to fight against any pathogenic bacterias as well as against environmental stressors. The present review is a brief but informative compilation of the different essential and desirable traits of probiotics, their mode of action and their useful effects on fishes. The review also highlights the role of probiotics in helping the fishes to combat against the different physical, chemical and biological stress.     

Comparison of seed-derived with micropropagated male-sterile plants of Tagetes erecta L. for F1 hybrid seed production

Summary

To multiply large number of male-sterile marigold plants for F₁ hybrid seed production, an efficient protocol for in vitro cloning of field-grown differentiated male sterile plants has been developed. A comparative field performance study of tissue culture and seed-derived male sterile plants of two marigold genotypes was undertaken to test the possibility of using micropropagated plants in hybrid seed production. Tissue culture raised plants of both genotypes had superior field performance to the seed-derived counterparts. These plants were more vigorous in growth, i.e. in terms of plant height, number of secondary branches and number of leaves and plant spread, while the leaf chlorophyll contents were equal to that of seedling plants. Flowering was earlier by 2-3 weeks and the number of flowers per plant was also higher in such plants. Repeated hand pollination of sterile flowers with bagged flowers of cv. Pusa Narangi Gainda showed that seed set and bold seed yield were higher or almost comparable with the seed-derived plants. The results clearly indicate that the tissue culture can be adopted for the successful cloning of male-sterile plants, which could then be utilized for producing F₁ seeds with higher quantities of bold seeds with better storability.     

Nitrogen and vermicompost interaction on soil and leaf nutrient status of kinnow mandarin in vertisols of Jhalawar district

A field experiment entitled “nitrogen and vermicompost interaction on soil and leaf nutrient status of kinnow mandarin in vertisols of Jhalawar district” was conducted at the Fruit Research Farm, Department of Fruit Science, College of Horticulture and Forestry, Jhalawar (Rajasthan) during 2012–13 to study the effect of different levels of nitrogen and vermicompost on physico-chemical properties of soil and leaf micro and macro nutrient contents of Kinnow mandarin. The result indicated that application of T₁₅ treatment i.e. nitrogen at 350 g/plant + vermicompost 20 kg/plant was found best with regard to improvement in soil physico-chemical properties like organic carbon content (0.44%), available nitrogen (N) (379.36 kgha^?1), available phosphorus (P) (25.56 kgha^?1), available potassium (393.29 kgha^?1) and reduces electrical conductivity (0.34 dSm^?1), soil pH (7.42) and calcium carbonate (CaCO₃) content percentage (15.20) of soil.