Some plants like it warmer: Increased growth of three selected invasive plant species in soils with a history of experimental warming

Soil warming can affect plant performance by increasing soil nutrient availability through accelerating microbial activity. Here, we test the effect of experimental soil warming on the growth of the three invasive plant species Trifolium pratense (legume), Phleum pratense (grass), and Plantago lanceolata (herb) in the temperate-boreal forest ecotone of Minnesota (USA). Plants were grown from seed mixtures in microcosms of soils with three different warming histories over four years: ambient, ambient +1.7 °C, and ambient +3.4 °C. Shoot biomass of P. pratense and P. lanceolata and plant community root biomass increased significantly in soils with +3.4 °C warming history, whereas T. pratense responded positively but not significantly. Soil microbial biomass and N concentration could not explain warming effects, although the latter correlated significantly with the shoot biomass of P. lanceolata. Our results indicate that soil with a warming history may benefit some invasive plants in the temperate-boreal ecotone with potential impacts on plant community composition. Future studies should investigate the impact of warming-induced differences in soil organisms and nutrients on plant invasion.     

Pretreatment of diesel-contaminated hydrophobic soil using surfactant and sodium hexa-metaphosphate (Na-HMP) to improve infiltration of aqueous phase remedial agents in unsaturated soil

Journal of Soils and Sediments - The remediation of diesel-contaminated hydrophobic soil is difficult due to the inability of aqueous phase remedial agents to infiltrate the soil. This novel...     

Rhizobacteria‐mediated resistance against the blackeye cowpea mosaic strain of bean common mosaic virus in cowpea (Vigna unguiculata)

BACKGROUND: The present study investigated the effect of seven Bacillus‐species plant‐growth‐promoting rhizobacteria (PGPR) seed treatments on the induction of disease resistance in cowpea against mosaic disease caused by the blackeye cowpea mosaic strain of bean common mosaic virus (BCMV). RESULTS: Initially, although all PGPR strains recorded significant enhancement of seed germination and seedling vigour, GBO3 and T4 strains were very promising. In general, all strains gave reduced BCMV incidence compared with the non‐bacterised control, both under screen‐house and under field conditions. Cowpea seeds treated with Bacillus pumilus (T4) and Bacillus subtilis (GBO3) strains offered protection of 42 and 41% against BCMV under screen‐house conditions. Under field conditions, strain GBO3 offered 34% protection against BCMV. The protection offered by PGPR strains against BCMV was evaluated by indirect enzyme‐linked immunosorbent assay (ELISA), with lowest immunoreactive values recorded in cowpea seeds treated with strains GBO3 and T4 in comparison with the non‐bacterised control. In addition, it was observed that strain combination worked better in inducing resistance than individual strains. Cowpea seeds treated with a combination of strains GBO3 + T4 registered the highest protection against BCMV. CONCLUSION: PGPR strains were effective in protecting cowpea plants against BCMV under both screen‐house and field conditions by inducing resistance against the virus. Thus, it is proposed that PGPR strains, particularly GBO3, could be potential inducers against BCMV and growth enhancers in cowpea. Copyright © 2009 Society of Chemical Industry     

Effects of Moisture Stress and Anti-transpirants on Leaf Chlorophyll,

Brinjal plants ( Solanum melongena L.) grown under moisture stress conditions in a glasshouse were treated with three anti-transpirants, namely cycocel, limewash and potassium chloride, to study their influence on chlorophyll content, soluble protein and photosynthetic rate. Moisture stress imposed at each of the three growth stages decreased chlorophyll content, soluble protein and photosynthetic rate. Of the anti-transpirants investigated, cycocel performed better than limewash and po-tassium chloride.     

Effect of seaweed sap as foliar spray on growth and yield of hybrid maize

Seaweeds are important marine renewable resources. Use of seaweeds as fertilizers has allowed for substitution in place of conventional synthetic fertilizers. This study was conducted to examine the effect of seaweed liquid extract (SLE) on growth, yield, and nutrient uptake by hybrid maize. The experiments were conducted in ZARS, Vishweshwaraiah Canal farm, Mandya (Karnataka, India) during the rabi season of 2011–2013 to study the effect of foliar applications of Kappaphycus alvarezii (K sap) and Gracilaria edulis (G sap) sap on growth and yield response of hybrid maize “NAH 1137”. Three foliar sprays of both saps were applied at the rate of 2.5, 5.0, 7.5, 10, and 15.0% (v/v) along with water spray as a control at different stages of the crop. It was found that grain yield increased significantly by 18.54% and 26.04% for plants receiving 10% concentrations of both K. alvarezii and G. edulis sap respectively, over control. The increase in yield was attributed to increase in the number of rows in cob, cob length, and 100 grain weight. This investigation concludes that application of both the saps at 10% increased the nutrient uptake, grain, and stover yield over control.     

Factors determining the adoption of laser land leveling in the irrigated rice–wheat system in Haryana,India

Laser land leveling has been increasingly adopted in the irrigated rice (Oryza sativa L.)–wheat (Triticum aestivum L.) cropping system in the state of Haryana (India), located in the north-western Indo-Gangetic Plains. Still, many farmers have applied it to only a fraction of their land. In this study, we used data collected from 621 farm households in Haryana and applied a double-hurdle model for assessing the factors that determine the adoption and intensity of laser-leveling technology. The results show that large land holders are more likely to laser level their farm land; however, we found a negative association between land holdings and the proportion of laser-leveled land. Information about technology through farmer-to-farmer communication and through private traders, participation in agricultural training and membership in local agricultural institutions increased both the likelihood and the intensity of adoption. Our findings call for a closer collaboration among the various stakeholders, specifically to promote farmer-to-farmer communication through increased participation in local institutions and increase the rate of adoption of laser leveling technology.     

Integrated rearing system approach in the farming of mud crab,shrimp, fish,oyster and periphyton in bracksihwater pond

Diversification of production systems has been identified as one of the major strategies for the long‐term sustainability of brackishwater aquaculture. On the context of diversification, a 180‐day culture experiment was carried out where four farming systems were tested: monoculture of mud crab, Scylla serrata (T1), polyculture of mud crab, with mullet Mugil cephalus and shrimp Penaeus indicus (T2), polyculture of mud crab with mullet, shrimp and oyster Crassostrea cuttackensis (T3), polyculture of mud crab with mullet, shrimp, oyster along with periphyton net (T4) covering 10% of the water spread area. There was no significant difference in the growth performances of mud crab, shrimp and oyster among the treatment but a significantly higher (p < .05) final average body weight (ABW) of M.cephalus was recorded in T4 (121.19 ± 2.09 g). Production considering only the fed animals (excluding oyster) was significantly (p < .05) higher in T4 (2,115 kg/ha) compared to other treatments. The overall water quality parameters do not vary significantly (p > .05) among the treatment ponds. Although there was no significant difference in total ammonia nitrogen (TAN) and nitrite‐N, highest value was recorded in T2 (56.23 ± 39.47 µg/L and 185.53 ± 110.71 µg/L) and T1 (55.78 ± 32.26 µg/L and 180.83 ± 103.65 µg/L). The results from the current experiment based on water quality and growth of animals showed that there is no negative interaction between the mud crab and other animals stocked in the polyculture pond which indicated that polyculture provides an efficient and sustainable utilization of resources.     

QTLs associated with resistance in soybean PI567516C to synthetic nematode population infecting cv. Hartwig

Worldwide, soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is the most destructive pathogen of soybean [Glycine max (L.) Merr.]. Crop losses are primarily mitigated by the use of resistant cultivars. Nematode populations are variable and have adapted to reproduce on resistant cultivars over time because resistance primarily traces to two soybean accessions, Plant Introduction (PI) 88788 and Peking. Soybean cultivar Hartwig, derived primarily from PI437654, was released for its comprehensive resistance to most SCN populations. A synthetic nematode population (LY1) was recently selected for its reproduction on Hartwig. The LY1 nematode population currently infects known sources of resistance except soybean PI567516C; however, the resistance to LY1 has not been characterized. The objective of this study was to identify quantitative trait loci (QTLs) underlying resistance to the LY1 SCN population in PI567516C, identify diagnostic DNA markers for the LY1 resistance, and confirm their utility for marker-assisted selection (MAS). Resistant soybean line PI567516C was crossed to susceptible cultivar Hartwig to generate 105 recombinant inbred lines (F₂-derived F₅ families). QTLs were mapped using simple sequence repeats (SSRs) covering 20 Linkage Groups (LGs) and three diagnostic markers, Satt592, Satt331, and Sat_274, were identified on LG O. These markers have a combined efficacy of 90% in identifying resistant lines in a second cross that has been generated by crossing a susceptible cultivar 5601T with resistant PI567516C. F₂-derived F₄ segregating population was used in MAS to identify resistant lines.