The ATAF1 transcription factor： At the convergence point of ABA-dependent plant defense against biotic and abiotic stresses

Because of their sessile lifestyle, plants have evolved sophisticated ways of coping with the various biotic and abiotic stresses they can encounter during their life. Their defensive reactions to a given stress have to be rapid and well adapted to the situation. They are the results of tightly coordinated changes at the molecular level involving the contributions of different signaling pathways. Traditionally, two signal transduction pathways have been investigated preferentially for defense against biotic stresses,

Interplay between nitric oxide and sulfur assimilation in salt tolerance in plants

Nitric oxide(NO),a versatile molecule,plays multiple roles in plant growth and development and is a key signaling molecule in plant response to abiotic stress.Nutrient management strategy is critical for abiotic stress alleviation in plants.Sulfur(S) is important under stress conditions,as its assimilatory products neutralize the imbalances in cells created by excessive generation of reactive oxygen species(ROS).NO abates the harmful effects of ROS by enhancing antioxidant enzymes,stimulating S assimilation,and reacting with other target molecules,and regulates the expression of various stress-responsive genes under salt stress.This review focuses on the role of NO and S in responses of plants to salt stress,and describes the crosstalk between NO and S assimilation in salt tolerance.The regulation of NO and/or S assimilation using molecular biology tools may help crops to withstand salinity stress.

Nitrogen in Relation to Photosynthetic Capacity and Accumulation of Osmoprotectant and Nutrients in Brassica Genotypes Grown Under Salt Stress

Different strategies of the application of nutrients are required to overcome the adverse effects of mustard （Brassica juncea L.） in response to NaCl stress. The objective of the present study was to determine if different added levels of nitrogen （N） in growth medium could alleviate the adverse effects of salt stress on photosynthetic capacity and accumulation of osmoprotectants and nutrients. 14 days mustard seedlings of salt-sensitive （cv. Chuutki） and salt-tolerant （cv. Radha） genotypes were fed with： （i） 0 mmol L^-1 NaCl ＋ 0 mg N kg^-1 sand （control）, （ii） 90 mmol L^-1 NaCl ＋ 30 mg N kg^-1 sand, （iii） 90 mmol L^-1 NaCl ＋60 mg N kg^-1 sand, （iv） 90 mmol L^-1 NaCl ＋90 mg N kg^-1 sand and （v） 90 mmol L^-1NaCl＋ 120 mg N kg^-1 sand. Under the condition of salinity stress, N application caused a significant ameliorative effect on both genotypes with respect to growth attributes [fresh weight （FW） and dry weight （DW）] and physio-biochemical parameters [percent water content （WC）, net photosynthetic rate （PN）, stomatal conductance （gs）, total chlorophyll （Ch1）, carbonic anhydrase （CA） activity and malondialdehyde （MDA）, nitrogen （N）, potassium （K） and sodium （Na） contents, and K/Na ratio] and yield attributes （number of pods/plant, seeds/pod and seed yield/plant）. The salt-tolerant genotype exhibited maximum value for growth, physio-biochemical and yield attributes at 60 mg N kg 1 sand than that of salt-sensitive genotype. These results suggest that application of N may ameliorate most of the attributes and prove to be a physiological remedy to increase the tolerance against the ill effects of salt stress in Brassicas.

Interactive Effect of GA_3 ,N and P Ameliorate Growth, Seed and Fibre Yield by Enhancing Photosynthetic Capacity and Carbonic Anhydrase Activity of Linseed: A Dual Purpose Crop

Linseed （Linum usitatissimum L.） is an important dual-purpose, industrial crop. Its seeds are used for the extraction of oil and stem for fibres. However, the production of linseed is not going parallel with the increasing demand of its products. The present work was carried out with an aim to find out whether exogenous application of gibberellic acid （GA3） with or without graded levels of nitrogen （N） and phosphorus （P） could improve the performance of three linseed genotypes Parvati, Shekhar and Shubhra together with minimizing the costly fertilizer input and losses. Four combinations of N and P, viz., 0 mg N＋0 mg P kg-1 soil （N0P0）, N13.4 P4.46 , N26.8P8.94 and N40.2P13.4 were constituted. Half dose of each combination was applied basally at the time of sowing and remaining half dose was given at 40 d after sowing （DAS） as foliar spray along with 10-6 mol L-1 GA3 . Prior to sowing, the seeds of each linseed genotype were grouped in to two, one group of seeds was soaked in 0 mol L-1 GA3 （control） and the other group was soaked in 10-6 M GA3 solution, each for 8 hours. Treatments were comprised of （i） 0 mol L-1 GA3＋N0P0 （T0 , control）, （ii） 10-6 mol L-1 GA3 ＋ N13.4P4.46 （T1）, （iii） 10-6 mol L-1 GA 3 ＋N 26.8 P 8.94 （T2） and （iv） 10-6 mol L-1 GA3＋N40.2P13.4 （T3）. The crop performance was assessed in terms of growth, physiological and biochemical parameters at 60 and 75 DAS and yield attributes at harvest （175 DAS）. The results showed a parallel increase in most of the parameters with increasing levels of N and P. However, application of 10-6 mol L-1 GA3 in association with N26.8P8.94 proved best, it enhanced seed yield, oil yield and fibre yield by 83.3, 97.3 and 78.7%, respectively accompanied with increase in net photosynthetic rate, carbonic anhydrase activity and dry matter accumulation. Among the genotypes tested, Shubhra performed best, while Parvati the least for most of the parameters studied. Thus, combined application of 10-6 mol L-1 GA3 plus N26.8P8.94 proved best and can be recommended to exploit the linseed as a dual-purpose crop for good yield of seed and fibre.

Growth and Economic Assessment of Wheat under Tillage and Nitrogen Levels in Rice-Wheat System

Mechanically post-harvest puddled rice field has stubbles that often delay timely planting of winter wheat crop. Zero tillage increased the net return by decreasing the unwise tillage operations and labor charges. Keep in view, a randomized complete block design experiment in a split plot arrangement was conducted with four tillage system [conventional tillage, CT;deep tillage, DT;zero tillage with zone disc tiller, ZDT;and happy seeder, HS] in main plots and five nitrogen levels [0, 75, 100, 125, and 150 kg&middot;ha-1] in subplots during 2009 to 2010 and 2010 to 2011 cropping seasons. Results showed that in 2009-10 and 2010-11 grain yield (4.6 Mg&middot;ha-1 and 5.7 Mg&middot;ha-1) in DT and (4.5 Mg&middot;ha-1 and 5.8 Mg&middot;ha-1) in HS were significantly higher compared with CT and ZDT. Significantly, maximum leaf area index (5.18 and 5.24) and crop growth rate (12.14 g&middot;m-2&middot;d-1 and 13.15 g&middot;m-2&middot;d-1) were noted in DT. Grain protein (11.78%) was significantly higher in DT compared with CT, ZDT, and HS during 2009-10 and 2010-11. Total yield (12.4 Mg&middot;ha-1 and 16.4 Mg&middot;ha-1) and grain yield (4.9 Mg&middot;ha-1 and 6.5 Mg&middot;ha-1) at N125 kg&middot;ha-1 while grain protein (13.52%) at N150 kg&middot;ha-1 was significantly higher than other nitrogen levels. Maximum LAI (5.08 and 5.51) and crop growth rate (14.68 g m-2&middot;d-1 and 15.77 g<span style='font-family:Verdana, Helvetica, Arial;white-space:normal;

Chemical Control of Monocot Weeds in Wheat (<i>Triticum aestivum</i>L.)

Due to similar growth pattern and morphology, monocot weeds offer more severe competition with wheat. A field experiment was conducted to screen herbicides most suitable for the control of monocot weeds in wheat. Seven herbicides viz., Puma super 69EW @ 862.5 g a.i. ha-1, Bristle 69 EW @ 1250 ml, Topik 15WP @ 37.05 g a.i. ha-1, Safener15WP @ 247g, Certain 80WD @ 395.2 g and Tremor 24EC @ 247 ml/ha were used. Weedy check where no weed control was practiced was kept as control. All herbicides were sprayed as post-emergence with second irrigation 38 days after crop sowing. The best weed control was accomplished by Safener 15WP 247 g ha-1 as significantly lower weed counts per m2 (11.0) and higher percent weed control (73.4%) were noted after 21 days of its spray. Wheat growth parameters like plant height, number of tillers per m2, spike length and number of spikelets per spike remained statistically at par among various treatments. Significantly higher number of grains per spike (55.67) and 1000 grain weight (36 g) were noted with Puma Super 69EW @ 1250 ml ha-1 and Certain 80WD 395.2 g ha-1, respectively. Although treatments did not differ significantly with respect to wheat grain and biological yields, yet the highest grain yield (3708.3 kg ha-1) and biological yield (10208.3 kg ha-1) were produced by Puma Super 69EW @ 1250 ml ha-1. Based on better weed control and wheat yield, Safener 15WP @ 395.2 ml ha-1 and Puma Super 69EW @ 1250 ml ha-1 were proved to be better in areas where wheat fields are predominantly infested by monocot weeds. Puma super, Bristle Tremore, Safener and Certain were found effective against Avena fatua and Polypogon monspelliensis, less effective against Phalaris minor and ineffective against Poaannua grass.

Down-regulation of Fra a 1.02 in strawberry fruits causes transcriptomic and metabolic changes compatible with an altered defense response

The strawberry Fra a 1 proteins belong to the class 10 Pathogenesis-Related(PR-10)superfamily.In strawberry,a large number of members have been identified,but only a limited number is expressed in the fruits.In this organ,Fra a 1.01 and Fra a 1.02 are the most abundant Fra proteins in the green and red fruits,respectively,however,their function remains unknown.To know the function of Fra a 1.02 we have generated transgenic lines that silence this gene,and performed metabolomics,RNA-Seq,and hormonal assays.Previous studies associated Fra a 1.02 to strawberry fruit color,but the analysis of anthocyanins in the ripe fruits showed no diminution in their content in the silenced lines.Gene ontology(GO)analysis of the genes differentially expressed indicated that oxidation/reduction was the most represented biological process.Redox state was not apparently altered since no changes were found in ascorbic acid and glutathione(GSH)reduced/oxidized ratio,but GSH content was reduced in the silenced fruits.In addition,a number of glutathione-S-transferases(GST)were down-regulated as result of Fra a 1.02-silencing.Another highly represented GO category was transport which included a number of ABC and MATE transporters.Among the regulatory genes differentially expressed WRKY33.1 and WRKY33.2 were down-regulated,which had previously been assigned a role in strawberry plant defense.A reduced expression of the VQ23 gene and a diminished content of the hormones JA,SA,and IAA were also found.These data might indicate that Fra a 1.02 participates in the defense against pathogens in the ripe strawberry fruits.

Nanopesticides and Nanofertilizers and Agricultural Development: Scopes, Advances and Applications

Excessive use of pesticides and fertilizers in agriculture in order to increase yields has proved unnecessary because a large part of them remain unused and have negative effects on the environment and human health. Therefore, it is a great challenge for farmers to replace the application of pesticides and fertilizers with nanopesticides and nanofertilizers, with the aim of reducing the use of mineral fertilizers and increasing yields, as well as supporting agricultural development. This review provides a detailed overview of the classification of pesticides, commonly used nanoparticles in agriculture and their function, as well as impact of nanopesticides and nanofertilizers on the environment. The application of nanopesticides and nanofertilizers and new delivery mechanisms to improve crop productivity are reviewed and described. Particularly, the advantage of the nanoencapsulation process is emphasized for both pesticides and fertilizers. For hydrophobic pesticides, it may be a tool to provide greater stability, dispersion in aqueous media, and allowing a controlled release of the active compound, which increases its effectiveness. In nanofertilizers, micro- or macronutrients can be encapsulated by nanomaterials which allow to release of nutrients into the soil gradually and in a controlled way maintaining soil fertility, thus preventing eutrophication and pollution of water resources. Risks assessment of application of nanopesticides and nanofertilizers in agriculture are required for their correct and safe application.

Chemical Composition and Biological Significance of Thymol as Antiparasitic

Thymol is one of the most important phytochemical components because of its pharmacological and bioactive potential effects. This review focuses particularly on thymol as an alternative natural antiparasitic with potential use in the pharmaceutical industry. This is in line with the preferences of the natural products for treatment being safer and without side effects. The biosynthesis pathways of thymol and carvacrol have been discussed, and mechanism of action of thymol on parasites. Studies on thymol confirmed the activity of thymol as anti-parasite against anthelmintic, Trypanosoma ssp., Toxoplasma gondii, Leishmania spp., Plasmodium falciparum, Giardia duodenalis, Eimeria ssp., Cryptosporidium baileyi and Cryptosporidium galli.

Pineapple (<i>Ananas comosus</i>L. Merr.), Waste Streams, Characterisation and Valorisation: An Overview

Processing pineapple industry produces huge amounts of waste thus contributing to worsen the global environmental problem. Valorising pineapple waste through further processing until it is transformed into valuable products using environmentally friendly techniques is both, a challenge, and an opportunity. The aim of this review is to characterize and highlight the phytochemical constituents of pineapple peel, their biological activity, and to evaluate the current state-of-art for the utilization of pineapple waste from the processing industry for obtaining pharmaceuticals, food, and beverages, biocombustibles, biodegradable fibers, and other different usage. Pineapple residues are rich in many bioactive compounds such as ferulic acid, vitamin A and C as antioxidant, and containing alkaloids, flavonoids, saponins, tannins, cardiac glycoside, steroids, triterpenoids and phytosterols may provide a good source of several beneficial properties, as well as bromelain that showed significant anticancer activity. Also, pineapple processing residues contain important volatile compounds used as aroma enhancing products and have high potential to produce value-added natural essences. Pineapple peels can be used as nonpharmacological therapeutical in the form of processed food and instant drinks;its potent natural antimicrobial properties may be applied for food conservation and as potential leads to discover new drugs to control some infectious microbial. Pineapple waste is a promising source of metabolites for therapeutics, functional foods, and cosmeceutical applications.

Multiscale assessment of ground,aerial and satellite spectral data for monitoring wheat grain nitrogen content

Wheat grain quality characteristics have experienced increasing attention as a central factor affecting wheat end-use products quality and human health.Nonetheless,in the last decades a reduction in grain quality has been observed.Therefore,it is central to develop efficient quality-related phenotyping tools.In this sense,one of the most relevant wheat features related to grain quality traits is grain nitrogen content,which is directly linked to grain protein content and monitorable with remote sensing approaches.Moreover,the relation between nitrogen fertilization and grain nitrogen content(protein)plays a central role in the sustainability of agriculture.Both aiming to develop efficient phenotyping tools using remote sensing instruments and to advance towards a field-level efficient and sustainable monitoring of grain nitrogen status,this paper studies the efficacy of various sensors,multispectral and visible red-greenblue(RGB),at different scales,ground and unmanned aerial vehicle(UAV),and phenological stages(anthesis and grain filling)to estimate grain nitrogen content.Linear models were calculated using vegetation indices at each sensing level,sensor type and phenological stage.Furthermore,this study explores the up-scalability of the best performing model to satellite level Sentinel-2 equivalent data.We found that models built at the phenological stage of anthesis with UAV-level multispectral cameras using red-edge bands outperformed grain nitrogen content estimation(R2=0.42,RMSE=0.18%)in comparison with those models built with RGB imagery at ground and aerial level,as well as with those built with widely used ground-level multispectral sensors.We also demonstrated the possibility to use UAV-built multispectral linear models at the satellite scale to determine grain nitrogen content effectively(R2=0.40,RMSE=0.29%)at actual wheat fields.

Effect of Salicylic Acid on Salinity-induced Changes in Brassica juncea

Seeds of Indian mustard （Brassicajuncea （L.） Czern. et Coss.） were exposed to 0, 50, 100 and 150 mmol/L NaCI for 8 h and seeds were sown in an earthen pot. These stressed seedlings were subsequently sprayed with 10μmol/L salicylic acid （SA） at 30 d and were sampled at 60 d to assess the changes in growth, photosynthesis and antioxidant enzymes. The seedlings raised from the seeds treated with NaCI had significantly reduced growth and the activities of carbonic anhydrase, nitrate reductase and photosynthesis, and the decrease was proportional to the increase in NaCI concentration. However, the antioxidant enzymes （catalase, peroxidase and superoxide dismutase） and proline content was enhanced in response to NaCI and/or SA treatment, where their interaction had an additive effect. Moreover, the toxic effects generated by the lower concentration of NaCI （50 mmol/L） were completely overcome by the application of SA. It was, therefore, concluded that SA ameliorated the stress generated by NaCl through the alleviated antioxidant system.

Crop phenotyping in a context of global change:What to measure and how to do it

High-throughput crop phenotyping,particularly under field conditions,is nowadays perceived as a key factor limiting crop genetic advance.Phenotyping not only facilitates conventional breeding,but it is necessary to fully exploit the capabilities of molecular breeding,and it can be exploited to predict breeding targets for the years ahead at the regional level through more advanced simulation models and decision support systems.In terms of phenotyping,it is necessary to determined which selection traits are relevant in each situation,and which phenotyping tools/methods are available to assess such traits.Remote sensing methodologies are currently the most popular approaches,even when lab-based analyses are still relevant in many circumstances.On top of that,data processing and automation,together with machine learning/deep learning are contributing to the wide range of applications for phenotyping.This review addresses spectral and red-green-blue sensing as the most popular remote sensing approaches,alongside stable isotope composition as an example of a lab-based tool,and root phenotyping,which represents one of the frontiers for field phenotyping.Further,we consider the two most promising forms of aerial platforms(unmanned aerial vehicle and satellites)and some of the emerging data-processing techniques.The review includes three Boxes that examine specific case studies.

Phenotyping Tomato Root Developmental Plasticity in Response to Salinity in Soil Rhizotrons

Plants have developed multiple strategies to respond to salt stress.In order to identify new traits related to salt tolerance,with potential breeding application,the research focus has recently been shifted to include root system architecture(RSA)and root plasticity.Using a simple but effective root phenotyping system containing soil(rhizotrons),RSA of several tomato cultivars and their response to salinity was investigated.We observed a high level of root plasticity of tomato seedlings under salt stress.The general root architecture was substantially modified in response to salt,especially with respect to position of the lateral roots in the soil.At the soil surface,where salt accumulates,lateral root emergence was most strongly inhibited.Within the set of tomato cultivars,H1015 was the most tolerant to salinity in both developmental stages studied.A significant correlation between several root traits and aboveground growth parameters was observed,highlighting a possible role for regulation of both ion content and root architecture in salt stress resilience.