Inter tree variability for fruit quality in jackfruit selections of Western Ghats of India

Ninety-five jackfruit types selected from Western Ghats of India, which is the centre of origin for the species, were analyzed using Mahalanobis D² technique to determine the degree of divergence present among the selections. The studies revealed that majority of selections (91), irrespective of their ecogeographic area, were grouped in one cluster and the remaining 4 types were solitary with one selection in each cluster. Inter cluster distance was maximum between clusters D and E (525.8) and minimum inter cluster divergence was observed between clusters B and C (106.1). Cluster means for all economically important characters were not found to be highest in any one cluster indicating the vast diversity on account of indigenous and cross-pollinated nature of the crop. The maximum relative contribution to the total divergence was by number of seeds per fruit and TSS:Acid ratio indicating the ample amount of variability in these traits and hence the selection process for crop improvement in jackfruit should deem these characters.     

Ethnomedical knowledge of plants used by Kunabi Tribe of Karnataka in India

Therapeutic effects and medicinal efficacy of the wild herbs were identified and administered by the tribal people to cure various ailments. Recently, the practice of herbal medicine has been diminishing, which may lead to the loss of valuable information about healing herbs. The Uttara Kannada District of Karnataka in India is one of the rich biodiversity centers of Western Ghats. Many tribes like Gowlis, Siddis, Halakki Okkaligas and Kunabis inhabit the semi-evergreen forests of the District. The mixed marathi speaking Kunabis have migrated from Goa and settled here a long time back and are even today without modern facilities. Thus, in the way of revitalization of traditional herbal medicines, it is an effort to record the valuable ethnomedical knowledge of the tribe Kunabis of Uttara Kannada District in Karnataka. A total of 45 species of plants used by Kunabi community people are described here based on an ethnomedical field survey. These plants belong to 26 families and are used to treat a wide range of discomforts like fever, cough, skin diseases, rheumatism, snakebite, jaundice, dysentery, etc.     

Biophysical quantification of biodiversity and ecosystems services of forest ecosystems in the Western Ghats: a case study of Uttara Kannada District,India

Biodiversity and ecosystem services play key roles in future economic strategies seeking to promote development and prosperity. This study assesses the status of biodiversity and flow of ecosystem services from selected forest types in the Western Ghats. At the sampling sites, the number of tree species ranged from 16 to 79 per hectare depending on the forest type. The estimates for Shannon–Wiener index for trees in the evergreen, moist deciduous and dry deciduous forest plots were 3.02, 2.9 and 1.54, respectively. The total biomass carbon stocks in evergreen, moist deciduous and dry deciduous forests in the study area was 229, 221 and 189 t C/ha, respectively.Analysis of dependency patterns of local communities on forest resources indicated a high dependency on provisional services such as fuelwood, manure and fodder. The study records the highest dependency rates for fuelwood,ranging between 72 and 100% for the three forest types and indicates that forest ecosystems underpin the well-being of the population dependent directly and indirectly on them.     

Landraces of cowpea, <Emphasis Type="Italic">Vigna</Emphasis><Emphasis Type="Italic">unguiculata</Emphasis> (L.) Walp., as potential sources of genes for unique characters in breeding

Cowpea landraces belonging to Vigna unguiculata (L.) Walp. subsp. unguiculata cv.-gr. unguiculata and cv.-gr. sesquipedalis collected from part of the Deccan Plateau and West Coast of India were evaluated to (i) identify the diverse source(s) of variation for improved characters like pods/peduncle and seed index (ii) study the response of landraces for adaptation to drought and heat stress and (iii) understand the breeding value of a landrace in the genetic improvement of a popular cowpea cultivar. Landraces were evaluated for various morphological characters, pods/peduncle, seed index and other economically important agronomic traits, rust resistance and drought and heat tolerance in different years and environments. Landraces were found as an important source of genetic variability for pods/plant, pods/peduncle, better pod filling ability (seed index), grain yield/plant as well as drought and heat tolerance and rust resistance. Hybridization between C 152 (cv.) and DWDCC 016 (landrace) resulted in release of new variation not present in the two parents. Thus the landrace, DWDCC 016, can be utilized to improve cultivated varieties by transferring to them the economically valuable traits like pods/peduncle and seed index thereby enhancing realisation of sink potential and ultimately grain yield in a sustainable way.     

Discovery and characterization of sulfoxaflor, a novel insecticide targeting sap-feeding pests

The discovery of sulfoxaflor [N-[methyloxido[1-[6-(trifluoromethyl)-3-pyridinyl]ethyl]-λ(4)-sulfanylidene] cyanamide] resulted from an investigation of the sulfoximine functional group as a novel bioactive scaffold for insecticidal activity and a subsequent extensive structure-activity relationship study. Sulfoxaflor, the first product from this new class (the sulfoximines) of insect control agents, exhibits broad-spectrum efficacy against many sap-feeding insect pests, including aphids, whiteflies, hoppers, and Lygus, with levels of activity that are comparable to those of other classes of insecticides targeting sap-feeding insects, including the neonicotinoids. However, no cross-resistance has been observed between sulfoxaflor and neonicotinoids such as imidacloprid, apparently the result of differences in susceptibility to oxidative metabolism. Available data are consistent with sulfoxaflor acting via the insect nicotinic receptor in a complex manner. These observations reflect the unique structure of the sulfoximines compared with neonicotinoids.     

Morphology and genetics of a new found determinate genotype in chickpea

Chickpea (Cicer arietinum L.) is an indeterminate plant and produce excessive vegetative growth that acts as a competitive sink for developing pods resulting in reduced fruit set whenever soil moisture and temperature conditions are favorable. Determinate genotype was so far not available in the world chickpea germplasm. Determinate chickpea is needed to change its plant architecture in order to achieve a breakthrough in its productivity and stabilize yields in cool and long-season sub-tropical environments of semi-arid tropics. A true breeding determinate chickpea genotype was developed for the first time in the breeding programme. The objectives were to study: (i) the new found determinate genotype BGD 9971 for important plant characteristics and (ii) the genetics of determinate growth habit in it. Determinate genotype was bushy, compact and dwarf in its morphology; the stem growth terminated by a flower and produced 1–4 seeds per pod. The segregation patterns in the F₂ and F₃ of the two crosses (BGD 72 × BGD 9971 and BGD 128 × BGD 9971) involving indeterminate and determinate parents have shown that the determinate growth habit in BGD 9971 was governed by two recessive genes. The genes for determinacy in BGD 9971 were designated as dt1 and dt2. The homozygous recessive for both alleles (dt1dt1dt2dt2) produced a determinate phenotype. The utilization of genes identified for determinacy in the newly developed BGD 9971 has the major impact on chickpea breeding for better adaptation to cool climate, high fertility and irrigated environments.     

Spatial variation in drainage characteristics and geomorphic instantaneous unit hydrograph (GIUH); implications for watershed management—A case study of the Varada River basin,Northern Karnataka

Geomorphological characteristics can be treated as signatures of hydrological responses. Geomorphologic instantaneous unit hydrograph (GIUH) is of utmost use in planning watershed management programs on a broad scale in absence of hydrologic data. Fifth order basins from different agroclimatic zones in the Varada River basin were selected to understand the spatial variation in drainage characteristics. These sub-basins show significant differences in their morphometric properties such as basin area, drainage density, bifurcation ratio, circularity ratio, constant of channel maintenance etc. These differences reflect variation in the hydrological process and geomorphologic instantaneous unit hydrograph (GIUH) of different sub-basins and can be used to understand watershed management aspects. Fifth order sub-basin in the Southern Transition agroclimatic zone is potential for artificial recharge programs. Sub-basins in the Hilly non-forest zone on the north are ideal for surface water storage like tank development program while Forested Hilly zone on the north are environmentally sensitive and prone to erosion.     

Effect of understocking density of channel catfish fingerlings in intensively aerated multiple‐batch production

Multiple‐batch production is the most widely practiced method of raising channel catfish. Producers are increasingly adopting intensified production practices in multiple‐batch systems by increasing stocking density and aeration rates as a means to improve cost efficiencies. Proven stocking recommendations are required for the efficient implementation of recent developments in multiple‐batch production. Twelve 0.4‐ha ponds were understocked with 17,484, 20,612, and 26,124 fingerlings/ha (mean weight = 40 g/fish) over equal weights of carryover fish (0.46 kg/fish @ 4,589 kg/ha). Fish were fed once daily to apparent satiation with a 28% protein floating feed and aerated with a single 7.4‐kW electric paddlewheel aerator. Density‐dependent significant differences were absent for gross, net, daily net yields, marketable yields (≥0.54 kg), growth (g/day), and survival. Sub‐marketable yield (<0.54 kg) and feeding rate increased significantly with increased understocking density. Economic analysis revealed increased breakeven prices and diminished net returns with increased stocking density when sub‐marketable fish were not considered as revenue. These differences in production costs and profits among the three treatments became minimal when sub‐marketable fish were included as revenue. All three density treatments attained positive annual net cash flows. This study validates channel catfish understocking densities of 17,000–26,000 fish/ha to improve cost efficiency in intensively aerated, multiple‐batch production systems.