Search

Fruit yield depends on spray management techniques, i.e., uniformity, time, quantity, and precision of application. Due to variability in tree canopies, it is difficult to manage spray applications properly. Old orchard sprayers apply continuous spray without differentiating between size, density and spaces between canopies, causing drift losses and environmental hazards. Keeping this in view, conventional sprayer was modified to double sided vertical boom type sprayer, which was equipped with infrared sensors, solenoid valves and Arduino Mega microcontroller, programmed with Arduino IDE. Vertical booms consist of eight nozzles, four on each side, height and width of which were adjustable according to groove age. Each pair of nozzles was controlled independently for variable rate of application with respect to canopy characteristics. Spray coverage and vertical distribution of real time variable rate sprayer (RTVRS) were analyzed and compared with conventional sprayer. Average spray coverage at discharge rates, 800 and 1200 L/hr was 5.37, 9.18 μL/cm² with RTVRS and 3.87, 6.63 μL/cm² with conventional sprayer respectively. Vertical distribution was measured for 3 m canopy height, which was divided into 3 equal sections. Percent spray deposits of RTVRS were 22.2%, 54.06%, 23.78% and conventional sprayer were 17.75%, 59.03%, 23.17% from lower to upper section, while the skewness towards top was -0.35 and -0.48 respectively. RTVRS showed promising results as compared to conventional sprayer and better replacement to address the current issues related to farmers and environment. Moreover, the cost of production is also 5 to 10 times less than imported crop sprayers. [ABSTRACT FROM AUTHOR]

As many antagonistic plants are being continuously explored for their nematicidal potential against nematodes, therefore, in the present study two antagonistic plants viz. Cannabis sativa and Azadirachta indica at different doses viz. 0, 2.5, 5, 7.5, 10, 12.5 and 15 g per kg of the soil were evaluated against Meloidogyne javanica on peach with the objective to curtail reliance on hazardous chemicals. Soil amendments of both the plants significantly reduced number of galls, eggmasses and eggs per eggmass on peach, root, soil, and total populations and reproduction factor of the nematode. Both the plants caused statistically similar reductions in these parameters at all the concentrations with few exceptions. However, the reductions caused by C. sativa were comparatively more than those by A. indica. The maximum reductions were observed at a dose of 15 g per kg of soil while the reductions were found to be the minimum with the lowest dose of 2.5 g per kg of soil. Similarly, the per cent reductions over control caused by both the plants were found to be dose dependent. As the concentration of the plant material increased, there was a corresponding decrease in the values of these parameters and the relationships were found to be inversely proportional. It is concluded from the present study that incorporation of C. sativa and A. indica in the soil as organic amendments can work very well as nematicides and can be successfully used for controlling root-knot nematodes replacing traditional chemical treatments and avoiding environmental pollution. [ABSTRACT FROM AUTHOR]

This endeavor includes thirty grapes' genotypes grown in northern zones of Punjab, Pakistan to determine similarities and dissimilarities in forty-four morphological traits according to the descriptor "International Plant Genetic Resources Institute (IPGRI)". The relation between the genotypes was determined by principal component analysis (PCA), and similarity was worked out by using cluster analysis. The dendrogram divided the genotypes into two main groups with classes and subclasses. The variation present within the class was up to 81.72% while the difference between classes was 18.28%. The morphological quantitative traits such as bunch length, bunch width, bunch weight, peduncle length, the weight of 10 berries, number of berry in a bunch, berry length, and berry width were in the following range 27.50-11 cm, 13.75-5 cm, 583.56-77.70 g, 6.50-1.55 cm, 53.70-9.70 g, 354-28, 27.37-11.40 mm and 18.06-10.41 mm respectively, which indicated a wide level of diversity in the selected genotypes. Based on phenological attributes, "Regina", "Perlet", and "Early White" were found early maturing genotypes to prevent berry rotting due to monsoon rains at the final stage of ripening. The data generated in this study would be helpful to preserve the existing germplasm and be available for designing future breeding programs. [ABSTRACT FROM AUTHOR]

MicroRNA families are important regulators of plant resistance to diverse stressors, but the miRNA families expressed in response to drought, and the levels thereof, in sugarcane (an important commercial source of both sugar and biofuel) remain poorly understood. In the present study, we determined the expression profile of miRNA families synthesized by leaves of the drought-resistant cultivar ROC22 stressed by addition of PEG to the growth substrate. Totals of 23 conserved miRNA families and 34 new miRNA families were identified, and 438 putative target genes of 44 miRNA families were described. Expression analysis revealed that 11 miRNA families were differentially expressed in control and drought-exposed plants. Of these, nine families were up-regulated and two down-regulated. The potential targets of the 11 miRNA families were genes associated with plant growth and stress resistance, specifically SPBP, MYB, the AGO1-like gene, NCBP, BCP, CPI, and LSG. With the exceptions of SPBP, NCBP and BCP, the other genes were down-regulated in response to drought stress. Our preliminary identification of 11 relevant miRNA families expressed by ROC22, and their targets, suggest that these miRNA families may regulate the response to drought stress and forms a basis for planned future work. The other new miRNA families identified, along with their targets, may exert novel effects on various metabolic pathways relevant to sugarcane growth and development. [ABSTRACT FROM AUTHOR]

Pot experiment was carried out at different nitrogen levels in maize and peanut intercropping system to investigate the mechanisms that govern interactions between intercropped species in soil rhizosphere. Three different nitrogen levels 100%, 75% and 50% of normal nitrogen application rate were used in maize monoculture. Two peanut plants were intercropped with single maize plant per pot. Effect of reduced nitrogen application was investigated in soil rhizosphere by measuring soil enzymatic activity, nutrition, soil microbial diversity and composition. Phospholipid fatty acid (PLFA) was carried out to understand about composition of viable soil micro flora and community level physiological profile (CLPP) was applied to work out the microbial diversity. The results revealed that soil nutrition and enzymatic activities were higher in intercropping treatments as compared to mono-cropping with similar level of nitrogen. The results of PLFA analysis showed that intercropping inhibited the fungal population and promoted the bacterial community. The results of AWCD showed that 4 kinds of carbon utilization sources (carboxylic acid, polymer, amines & carbohydrates) increased by the decrease of nitrogen levels in intercropping treatments and other 2 kinds of carbon sources (phenolic acids & amino acids) showed different trend. Cluster analysis (CA) and Principal component analysis (PCA) carried out from the results of PLFA and CLPP indicated distinct separation amongst all treatments of monocropping and intercropping as well as with different level of nitrogen application that reflected a variation in soil microbial activity and composition. However intercropping treatment with 75% nitrogen level performed similar to 100% monocropping treatment of maize. The results revealed that by intercropping of peanut with maize can be used to decrease the dependence on artificial fertilizer which provides a convenient organic farming model for growers across the world. [ABSTRACT FROM AUTHOR]