Ameliorating drought stress in sugarcane (Saccharum spp.) using biostimulants

In India, abiotic stress, particularly drought, is known to affect sugarcane cultivation. Among various management strategies, application of biostimulants, especially those from seaweeds, offer promising results in containing yield loss due to drought stress. Here, we tested the efficacy of Sea6 liquid biostimulant formulation LBS6 in field condition along with conventional management practices for comparison purpose using two popular commercial varieties of sugarcane (Co 86032 and Co 0212). Drought stress imposed during formative phase of the crop and foliar application of sea6 liquid formulation was applied at 60, 90 and 120 days after planting (DAP). The effect of liquid formulation on mitigating drought stress was assessed by studying the growth, physiological, yield and yield traits at important pheno-phases of the crop. Results showed that, in Co 86032 shoot population of control was 100.5×103 ha-1 and drought was 85.1×103 ha-1 with mean reduction of 15.5% over control. Drought stress induced 11.4, 12.4, 9.8 and 5.0% reduction in plant height, leaf area index (LAI), chlorophyll content (SPAD value) and photochemical efficiency, respectively. In Co 0212, drought induced 10.15, 9.4, 10.5, 9.5 and 5.1% reduction in shoot population, plant height, LAI, SPAD value and photochemical efficiency, respectively. Under drought condition, in Co 86032, foliar application of KCl (2.5%) and seaweed extract LBS6(2 mL L-1) was observed comparatively higher cane yield of 92.9 t ha-1 and 89.5 t ha-1, with 18 and 16.5% yield improvement over untreated drought plot, respectively. In Co 0212, foliar application of KCl (2.5%) and seaweed extract LBS6 (2 mL L-1) recorded 99 and 93.5 t ha-1 with 18.5% and 15.2% yield improvement over untreated drought plot, respectively. Among the two varieties, Co 0212 performed better under drought situation with KCl (2.5%) spray demonstrating better physiological efficiency under stress, closely followed by of sea6 formulation LBS6 (2 mL L-1). Further, the drought management practices did not affect the juice quality parameters in both the tested varieties.

Liquid Bioformulation of Metarhizium Anisopliae is Effective for the Management of Cow Pea Mosaic Disease.

Liquid bioformulation of Metarhizium anisopliae amended with oils and adjuvants was prepared. Six oils viz., sunflower, safflower, soybean, mustard, arachnid and coconut oils at three different concentrations, 0.1, 0.5 and 1.0 per cent and three adjuvants viz., glycerol @ 5, 8 and 10 per cent; tween-80 @ 0.02, 0.04, 0.06 and 1.0 per cent and arachnid oil @ 1, 5 and 10 per cent were tested to see their effect on growth and development of M. anisopliae in the bioformulation. Liquid bioformulation of M. anisopliae amended with Glycerol (10.0%) + Sunflower oil (0.5%) was found significantly effective which showed 84.33 per cent and 94.93 per cent higher surface area covered and biomass production respectively than the control. Efficacy of the bioformulation was tested against cow pea aphid, Aphis craccivora in pot as well as field condition. Liquid formulation of M. anisopliae supplemented with Glycerol (10.0%) + Sunflower oil (0.5%) was found to be significantly effective causing aphid mortality of 80 per cent at 30 days after spraying with protection of secondary spread of cow pea mosaic disease up to 100 per cent and 96.03 per cent in pot and field condition respectively. Spraying liquid formulation of M. anisopliae amended with Glycerol (10.0%) + Sunflower oil (0.5%) at 15 days interval for twice proved to be the best treatment with highest yield of 24.03 t/ha with a cost benefit ratio of 1:7.95 as compared to control (11.20 t/ha).

Biodeterioration studies of thermoplastics in nature using indigenous bacterial consortium

Thermoplastics, poly vinyl chloride and low-density polyethylene were treated in the presence of indigenously developed bacterial consortium in laboratory and natural conditions. The consortium was developed using four bacteria, selected on the basis of utilization of PVC as primary carbon source, namely P. otitidis, B. aerius, B. cereus and A. pedis isolated from the plastic waste disposal sites in Northern India. The comparative in-vitro treatment studies as revealed by the spectral and thermal data, illustrated the relatively better biodegradation potential of developed consortium for PVC than the LDPE. Further, the progressive treatments of both the thermoplastics were conducted for three months under natural conditions. For this purpose, bioformulation of consortium was prepared and characterized for the viability up to 70 days of storage at 25±1ºC. The consortium treated polymer samples were monitored through SEM and FT-IR spectroscopy. Analytical data revealed the biodeterioration potential of the developed consortium for PVC and LDPE, which could help in disposing the plastic waste.