Genetic diversity within sweet sorghum (Sorghum bicolor (L.) Monech) accessions as revealed by RAPD markers

Genetic diversity was evaluated among twenty seven sweet sorghum germpalsm genotypes using random amplified polymorphic DNA (RAPD) polymorphic markers. RAPD markers were efficient and detected 93.4 per cent polymorphism among the accessions. All the genotypes were grouped into three clusters of which all the females came under one single cluster with exception of ICSB 293. Similarly all the males were evenly distributed except one genotype, SSV 74 which formed a distinct cluster itself. Hence, RAPD markers proved to very useful in estimating the genetic diversity among sweet sorghum accessions

Sweet sorghum - a potential alternate raw material for bio-ethanol and bio-energy

Sweet sorghum Sorghum bicolor (L.) Moench is a special purpose sorghum with a sugar-rich stalk, almost like sugarcane. Besides having rapid growth, high sugar accumulation, and biomass production potential, sweet sorghum has wider adaptability (Reddy and Sanjana 2003). Given that water availability is poised to become a major constraint to agricultural production in coming years (Ryan and Spencer 2001), cultivation of sugarcane becomes difficult. Sweet sorghum would be a logical crop option in lieu of sugarcane in such situations. Sweet sorghum can be grown with less irrigation and rainfall and purchased inputs compared to sugarcane. The sugar content in the juice extracted from sweet sorghum varies from 1623% Brix. It has a great potential for jaggery, syrup and most importantly fuel alcohol production (Ratnavathi et al. 2004a). The stillage after extraction of juice from sweet sorghum can be used for co-generation of power

An outbreak of Fall Armyworm in Indian Subcontinent : A New Invasive Pest on Maize

The Fall armyworm (Spodopterafrugiperda, J.E. Smith), an economically crucial polyphagous insect pest native totropical and subtropical regions of America has reached Asia and noticed first time in maize fields South Karnatakain the Indian subcontinent during May 2018, causing substantial damage to the crop. The pest has invaded mostof the maize growing area in India within a short period of two months posing a severe threat to maize growers,challenges to the scientific community and administrators. In the context of its economic importance and destructivenature, the identification, biology and life cycle, nature of damage and extent of yield loss, and managementof fall armyworm through cultural practices, mechanical and local controls, biological and synthetic pesticideshave been reviewed in detail in the present manuscript. Early planting and intercropping with non-host crops areessential cultural practices to reduce pest incidence. The crop which was monitored during the early vegetativestage showed a good response for synthetic pesticides, while crop damage was largest in late vegetative andpre-flowering stages. The pathways of the introduction of fall armyworm into Indian sub-continent are subjectto speculations, however considering the lack of diapause mechanisms, its high spreading ability, and wide hostplant range it is likely that the pest will soon be able to colonize most of tropical Asia. Hence, there is an urgentneed for developing ecologically sustainable, economically profitable, and socially acceptable integrated pestmanagement strategies to mitigate the impact of the fall armyworm in India and Asia

Combining ability and heterosis study for yield and it’s attributing traits in maize (Zea Mays L.)

Combining ability and heterosis was studied in maize for grain yield and its attributing traits using line x tester mating design. Significant general and specific combining ability variances were observed for all the charactersstudied indicating the importance of both additive and non-additive gene action for the expression of these traits. Among the parents GPM-4, GPM-38, GPM-608, GPM-688, GPM-759, GPM-648 and CI-4 were found to be good general combiners for days to 50% tasseling and days to 50% silking. Similarly, GPM-18, GPM-27, GPM-30 and GPM-606 were good combiners for grain yield. Among the test hybrids GH-1834 and GH-1813 were found to be promising recording significant SCA effects for Number of kernels/ row, cob length and cob girth. whereas, for 100 seed weight GH-1852 and GH-1819 and for grain yield GH-1862, GH-1843,GH-1852 and GH-1829 were found to be promising. Similarly, among the 64 F1 hybrids significant economic heterosis of 21.0 and 6.46 per cent over National and Popular private hybrid check was recorded by both the test hybrids GH-1809 and GH-1829 respectively. GGE biplot technique was used to understand the interrelationship between genotypes, testers and their interaction and it could explain the variation through two components PC1 (55.28 %) and PC2 (44.72 %). The parental line L5 (GPM-27) which falls on the ATC absicca showed the highest GCA effects for grain yield followed by L7  (GPM-30). Likewise, among the two testers CM-111 was able to discriminate more number of genotypes

Sustainable intensification of climate-resilient maize–chickpea system in semi-arid tropics through assessing factor productivity

Abstract Global trends show that the rapid increase in maize production is associated more with the expansion of maize growing areas than with rapid increases in yield. This is possible through achieving possible higher productivity through maize production practices intensification to meet the sustainable production. Therefore, a field experiment on “Ecological intensification of climate-resilient maize–chickpea cropping system” was conducted during consecutive three years from 2017–2018 to 2019–2020 at Main Agricultural Research Station, Dharwad, Karnataka, India. Results of three years pooled data revealed that ecological intensification (EI) treatment which comprises of all best management practices resulted in higher grain yield (7560 kg/ha) and stover yield compared to farmers’ practice (FP) and all other treatments which were deficit in one or other crop management practices. Similarly, in the succeeding winter season, significantly higher chickpea yield (797 kg/ha) was recorded in EI. Further EI practice recorded significant amount of soil organic carbon, available nitrogen, phosphorus, potassium, zinc, and iron after completion of third cycle of experimentation (0.60%, 235.3 kg/ha,21.0 kg/ha,363.2 kg/ha,0.52 ppm and 5.2 ppm respectively). Soil enzymatic activity was also improved in EI practice over the years and improvement in each year was significant. Lower input energy use was in FP (17,855.2 MJ/ha). Whereas total output energy produced was the highest in EI practice (220,590 MJ ha−1) and lower output energy was recorded in EI–integrated nutrient management (INM) (149,255 MJ/ha). Lower energy productivity was noticed in EI-INM. Lower specific energy was recorded in FP and was followed by EI practice. Whereas higher specific energy was noticed is EI–INM. Each individual year and pooled data showed that EI practice recorded higher net return and benefit–cost ratio. The lower net returns were obtained in EI-integrated weed management (Rs. 51354.7/ha), EI-recommended irrigation management (Rs. 56,015.3/ha), integrated pest management (Rs. 59,569.7/ha) and farmers’ practice (Rs. 67,357.7/ha) which were on par with others