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French bean (Phaseolus vulgaris L.) production is adversely affected by many pathogens and insect-pests worldwide. In the present investigation, effect of different bio-fortified composts, organic amendments, botanicals and pesticides were evaluated against diseases and insect- pests of french bean. The results showed that seed treatment and drenching with Trichoderma harzianum strain 11, followed by soil application of fortified farmyard manure resulted in the lowest root rot incidence, highest germination, vigour and yield in french bean. In another set of experiment, soil incorporation of Parthenium hysterophorus, Urtica dioicaandLantana camarawere found to reduce root rot incidence with high germination and pod yield. Among the bioproducts and botanicals tested, foliar spray of cow dung extract (50%) reduced angular leaf spot, rust and bacterial blight severity by 51, 69 and 25 per cent, respectively. Among the fungicides, foliar application of azoxystrobin 23 SC (0.1%) and difenoconazole 25EC (0.025%), also reduced angular leaf spot and rust severity by 93 and 90 per cent, respectively. Among different insect pest management strategies under field conditions, cartap hydrochloride and batain seed extract registered low sucking bug (Chauliops choprai) population. Integrated approaches including bio-agents, botanicals along with chemicals for managing these diseases and insect-pests were found appropriate options. Out of six different IPM modules evaluated, seed treatment with carbendazim along with foliar spray of 0.1% azoxystrobin and cartap hydrochloride resulted in lowest root rot, rust, angular leaf spot, bacterial blight and Chaulopsis choprai bug population in French bean.

Maize brown sheath spot (MBSS), a new disease of maize, was discovered while surveying for maize leaf and sheath blight diseases in the Indian states of Assam, Jharkhand, Meghalaya, Manipur, and Odisha. Maize is the third most important cereal after rice and wheat in India. Unlike banded leaf and sheath blight disease caused by Rhizoctonia solani, MBSS symptoms on maize were discrete and limited to sheaths only. Symptoms of MBSS in the field were initially water-soaked necrotic lesions of 1 to 2 cm in diameter on the lowermost leaf sheaths, which then progressed to the upper sheaths. Lesions coalesced and covered approximately 2 to 5% of the sheath area. Infected dried lower leaves were shed, whereas infected upper leaves remained on the stem. The pathogen was isolated, characterized morphologically, pathologically, and molecularly, and identified as Waitea circinata var. prodigus, a basidiomycete known to cause basal leaf blight of seashore paspalum. The internal transcribed spacer (ITS) sequence 2 (ITS2) of rDNA from MBSS isolates formed a well supported clade with known W. circinata var. prodigus isolates. Molecular morphometric analysis of the ITS2 regions of the five known varieties of W. circinata detected distinguishing variations in GC content, compensatory base changes (CBCs), hemi- CBCs, indels, and altered base-pairing of helices. Variation in these characteristics may indicate that varieties are distinct biological species within W. circinata sensu lato. The geographical distribution and potential impacts of MBSS on the maize crop in India necessitate further investigations of pathogen identification and disease management.

Maydis leaf blight, caused by Bipolaris maydis, is a serious foliar disease of maize distributed widely throughout the world and causing significant yield losses. The study aimed to describe stages of the infection process of B. maydis on maize leaves. The adaxial surfaces of maize leaves were inoculated with a conidial suspension of B. maydis and leaf samples were collected from 24 to 120 hrs after inoculation (hai). At 24 hai, the germ tubes from the germinated conidia and fungal hyphae attempted to penetrate the leaf through the stomata. These results provide new insight into the infection process of B. maydis on maize leaves and may contribute to the development of more effective management of maydis leaf blight.

Banded leaf and sheath blight disease caused by Rhizoctonia solani f. sp. sasakii is a major constraint of Kharif maize. Wide host range of pathogen, its ability to survive as sclerotia under adverse environmental conditions and lack of resistant sources are some of the bottlenecks in its management. To reduce our dependence on chemicals, experiment was conducted at five hot-spots in India viz., Ludhiana (PAU and Ladhowal), Delhi, Karnal and Pantnagar centres to study the effect of leaf stripping method on disease severity and yield parameters of present day maize hybrids of different maturity groups as well as speciality corn cultivars. Per cent disease control achieved with leaf stripping treatment in different cultivars varied from 16.66 to 54.76% being highest at PAU, Ludhiana centre and lowest at Pantnagar centre. Maximum percent increase in yield was observed at Delhi centre (28.37%) closely followed by PAU, Ludhiana centre (28.23%). Positive correlation (r) was observed between mean per cent disease control and mean percent increase in yield.

Maize brown sheath spot (MBSS), a new disease of maize, was discovered while surveying for maize leaf and sheath blight diseases in the Indian states of Assam, Jharkhand, Meghalaya, Manipur, and Odisha. Maize is the third most important cereal after rice and wheat in India. Unlike banded leaf and sheath blight disease caused by

Rhizoctonia solani, a devastating soil borne fungus inciting banded leaf and sheath blight (BLSB) disease is a constraint in maize production and improvement program. Rhizoctonia isolates collected from seven diverse maize cropping zones of India were examined for morphological and molecular variability. All the tested isolates caused symptoms of BLSB on maize and were also cross infective on rice and sugarcane hosts, but showed significant variability in hyphal diameter, mean hyphal cell size, weight, size and distribution of scleorotia, culture pigmentation, incubation period, pathogenicity and expression of symptoms. Neighbour joining cluster analysis placed the 62 isolates of R. solani into four major groups, A, B, C and D. Group A was more diverse and included isolates of diverse agro-ecological zones. The cluster analysis corresponded well with principle component analysis. Pathogenicity testing of R. solani isolates on maize genotype (CM 501) revealed highly variable virulence pattern of the pathogen population suggesting its high evolutionary potential, and hence adaptability to diverse geographical regions. The study reveals a strong evidence of inherent potential of the R. solani isolates to survive in diverse ecological zones and its probable spread to other maize cultivars across India. Sequence comparisons of the internal transcribed sequence-ribosomal DNA region of 62 isolates did not reveal much diversity among the isolates. Majority of the isolates (n = 61) clustered together with anastomosis group (AG) AG1-IA used as reference strain in the phylogram, distinct from AG1-IB, AG2–2IIIB and Waitea circinata used as reference strains. BLSB isolates representing distinct geographical locations shared identical sequences indicating long-distance dispersal of the pathogen. The study confirms that the genetic flexibility of the pathogen allows for its adaptation to variable ecological niches and long-distance introduction of new genotypes into the region. The study emphasizes that epidemiological studies may complement the molecular studies.

Seed is the basic unit of crop production and has greater contribution to environmental and cultural factors and is widely distributed in national and international trade. The seeds are found to be responsible for disease transmission because they carry a number of pathogens. The toxigenic fungal flora, existing in conjunction with food, largely includes genera Aspergillus, Fusarium, and Penicillium and, to a lesser extent, the genera Alternaria, Claviceps, and Stachybotrys. These economically important species of fungi produce significant mycotoxins. More than 400 mycotoxins are known to exist in nature. Contamination of foods and feeds with mycotoxins is a worldwide serious problem. The most important mycotoxins in terms of toxic effect on both humans and animals are aflatoxins (AFs), citrinin (CIT), cyclopiazonic acid (CPA), fumonisins (FBs), moniliformin (MON), ochratoxin A (OTA), deoxynivalenol (DON), nivalenol (NIV), T-2 toxin (T-2), patulin (PAT), zearalenone (ZEA), and ustiloxins. These mycotoxins have several adverse impacts on consumers, such as loss of human and animal lives, health-care and veterinary care costs, contaminated food and feed disposal costs, and huge investment in research and management of the mycotoxin problem. The mycotoxins induce diverse biological effects, which have been characterized on animals and humans. These toxic effects of mycotoxins include cytotoxic, carcinogenic, immune suppressive, nephrotoxic neurotoxic, mutagenic and estrogenic effects, etc.

Turcicum leaf blight of maize caused by the fungus Setosphaeria turcica is a serious foliar disease of maize distributed widely throughout the world and causing significant yield losses. The disease is more prevalent in humid weather with temperature between 20–28 °C and causes small cigar-shaped lesions to complete destruction of the foliage. Though there are several management practices available, identification and deployment of host plant resistance is a pragmatic approach to control the disease. However, qualitative resistance is unstable and breaks down easily by emergence of new races of the pathogen in maize necessitating the development of durable TLB resistant cultivars. Application of modern molecular tools and availability of high-density molecular marker data are expected to accelerate efforts to develop resistant hybrids. This review provides a focuses on current status, and future research needs especially biological control and sustainable integrated management strategies of TLB.

Maydis leaf blight (MLB), a serious foliar fungal disease of maize, may cause up to 40% losses in yield. The present studies were undertaken to identify the stable sources of MLB resistance, its inheritance study, and testing of MLB resistance linked markers from diverse background in the Indian adapted tropical maize genotypes. A set of 112 inbred lines were screened under artificially created epiphytotics conditions at three hotspot locations. Analysis across multi-locations revealed significant effects of genotypes and environments, and non-significant effects due to genotypes × environment interaction on disease incidence. A total of 25 inbred lines with stable resistance were identified across multi-locations. Inheritance of resistance was studied in six F1s and two F2s of resistant and susceptible parents. The null hypothesis of segregation of resistance and susceptible for mono and digenic ratios in two F2 populations was rejected by Chi-square test. The non-significant differences among the reciprocal crosses depicted the complete control of nuclear genome for MLB resistance. Partial dominance in F1s and normal distribution pattern in F2s of resistant and susceptible parents suggested polygenic nature of MLB resistance. Correlation studies in F2 populations exhibited significant negative correlation between disease score and days to flowering. Five simple sequence repeats (SSRs) markers, found associated to MLB resistance in different studies were unable to differentiate amongst MLB resistance and susceptible parents in our study. This emphasizes the need of fine mapping for MLB resistance in Indian germplasm. The identified stable sources of resistance and information on inheritance study can be used further in strengthening of resistance breeding against MLB.

Turcicum leaf blight of maize incited by Exserohilum turcicum (Pass.) Leonard and Suggs is the major limiting factor of maize production in temperate agro-ecologies. Disease management through host plant resistance is the most effective strategy. In the present study among 26 maize genotypes which were initially screened for resistance against E. turcicum under field conditions, 8 genotypes viz., PS 39, CML 451, CML 470, CML 472, VL 1030, VL 1018140, VL1018527 and SMI178-1 were found resistant when screened against twelve isolates of E. turcicum under artificial epiphytotic conditions. Eight genotypes viz., PS45, CML165, CML459, VL1249, VL0536, SMC-5, SMC-3 and KDL 211 were found moderately resistant with disease grade ranged from 2.1-2.5. These maize genotypes possess resistance to turcicum leaf blight can be used successfully in developing high yielding early maturing varieties for high altitude temperate agro-ecologies. The fungus E. turcicum is highly variable in nature. Variability studies on pathogenicity were conducted on twelve isolates of E. turcicum on eleven putative differential maize lines. During the present study a wide pathogenic variation was observed among the twelve isolates of E. turcicum. Cluster analysis on the basis of similarity or dissimilarity in reaction types exhibited by the differential hosts, clustered the isolates into 6 pathogenic groups. The isolates belonged to higher altitudes (Kti 10, Kti11, Kti5) were found to be more aggressive as compared to the isolates of low altitude areas.

Rhizoctonia solani f. sp. sasakii causing banded leaf and sheath blight disease is one of the important pathogens of maize. It has rapidly gained economic importance in several parts of world and has potential to inflict economic loss up to 100 %. The disease, which is more prevalent in humid weather with temperature of around 28 °C, poses challenge to maize growers due to its soil borne nature and lack of resistant cultivars. The disease is difficult to control through either fungicides or crop rotation alone. Inheritance studies have indicated digenic and oligogenic nature of disease resistance. Quantitative trait loci controlling banded leaf and sheath blight have recently been identified that would facilitate the development of maize hybrids resistant to this disease. Therefore, a combination of management practices is required for control of banded leaf and sheath blight. The present paper reviews the available information on various aspects such as distribution, yield loss, symptoms, pathogen life cycle, epidemiology, creation of artificial disease epiphytotics and its integrated management through cultural, biological, chemical and genetic means. The consolidated knowledge presented in this review should help better disease management and reduce crop loss due to banded leaf and sheath blight.

Garden pea (Pisum sativum L. var. hortense) is cultivated during winter in subtropical and early spring in temperate zones. The major constraint to its cultivation, especially in low- and mid-hills, is infection by the causal organism of powdery mildew. Varietal diversification is needed to develop early- and medium-duration resistance to powdery mildew. Breeding work was initiated to develop a high-yielding garden pea cultivar with medium maturity, dark green pods, and resistance to powdery mildew. ‘Vivek Matar 11’ is a new garden pea cultivar developed by hybridization between ‘Azad Pea 1’ × ‘PRS-18-6-4-5-1’. It is a medium maturity cultivar having attractive long green curved pods with 8–10 sweet seed/pod and is highly resistant to powdery mildew. Average green pod yield is 10–11 Mt·ha−1. It is suitable for cultivation under organic and inorganic conditions. This cultivar may be adapted to other temperate regions of the world.

Post-flowering stalk rot (PFSR) complex caused by Fusarium verticillioides (Sacc.) and Macrophomina phaseolina (Tassi) Goid, is among the important constraints that limits the productivity of maize ( Zea mays L.). The absence of high levels of stable resistant sources to the pathogens has necessitated the continued search and identification of new sources of resistance. The principal goal of this work was once to identify new sources of resistance to PFSR and validate their stability across multi-environments by multi-year testing. A set of 80 elite inbred lines screened in the field against PFSR for three consecutive years at four hotspots in India (Hyderabad, Ludhiana, New Delhi and Udaipur) under artificially created disease epiphytotics. The scores on the scale of 1 to 9 based on the disease reaction were recorded by splitting the stems of each plant. Significant (p=

Maize (Zea mays L.; 2N=20) is major staple food crop grown worldwide adapted to several biotic and abiotic stresses. Maydis leaf blight (MLB) and banded leaf and sheath blight (BLSB) are serious foliar fungal diseases may cause up to 40% and 100% grain yield loss, respectively. The present studies were undertaken to work out the efficacy of chemicals, botanicals and bioagents for the management of MLB and BLSB under field condition for two seasons Kharif 2014 and 2015. Five molecules (propiconazole 25 EC, hexaconazole 25 EC, carbendazim 50 WP, mancozeb 75 WP and carbedazim 12 WP + mancozeb 63 WP), two bioagents i.e. Trichoderma harzianum and T. viridae and three botanicals namely azadirachtin, sarpagandha and bel pathar were tested for their efficacy against MLB. Eight newer fungicides viz., difenconazole 250 SC, hexaconazole 5 EC, carbendazim 50WP, validamycin 3 L, tebuconazole 250 EC, trifloxystrobin 50 WG + tebuconazole 50 WG, azoxystrobin 250 EC and pencycuron 250 SC were evaluated against BLSB. Analysis revealed significant effects of propiconazole at 0.1%, carbendazim 12 WP + mancozeb 63 WP at 0.125% and sarpagandha leaves at 10% against MLB pathogen, whereas validamycin at 0.1% and trifloxystrobin 25 WG + tebuconazole 50 WG at 0.05% were found effective against BLSB. The slow rate of disease control virtually by the bioagents might have not shown instant effect on plant response to the yield enhancing components. The identified sources of management can be used further in strengthening the plant protection in maize against MLB and BLSB.

Ascochyta blight (AB) caused by Ascochyta rabei (Pass.) Labr. is one of the most important constraints that limits the productivity of chickpea (Cicer arietinum L.). The absence of high levels of stable resistant sources to the pathogen has necessitated the continued search and identification of new sources of resistance. The main aim of this work was to identify new sources of resistance to AB and validate their stability across multi-environments. A collection of 424 elite chickpea genotypes were evaluated for AB resistance under controlled environmental conditions in 2005–2006 at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, India. Fifty-one genotypes with AB severity ≤3.0 (based on the 1–9 scale) were selected for a second round of evaluation in 2006–2007 at ICRISAT. Based on the results obtained during both years, an Ascochyta Blight Nursery (ABN) was established to evaluate the selected 29 chickpea genotypes, including 4 germplasm lines, 24 breeding lines and a highly susceptible line. The nursery was evaluated at 3 locations (Almora, Dhaulakuan and Ludhiana) in India over three crop seasons (2007–2008, 2008–2009 and 2009–2010) and under controlled environment conditions at ICRISAT to further confirm the stable performance of these genotypes. Analysis of variance revealed highly significant effects of year, location (year), genotype and genotype × location (year) interaction. The genotype and genotype × environment (GGE) biplot analyses of multi-environment data showed that resistance of five genotypes (EC 516934, ICCV 04537, ICCV 98818, EC 516850 and EC 516971) had mean disease severity ≤3.0 on the 1–9 scale and the reactions were consistent across the environments. Genotype EC 516934 was found resistant to AB at the seedling stage in the controlled environment at ICRISAT. The remaining genotypes showed moderately resistant reaction (3.0–5.0) to AB under controlled environment conditions. A significant positive correlation was found between the performance of the genotypes under controlled environment and field screening conditions (r = 0.70; P

The high incidence of various soil-borne and foliar diseases is a major production constraint in the profitable cultivation of French bean. Compost and compost teas have been widely explored as an eco-friendly option for controlling plant diseases in container mixes. However, there is limited information regarding their disease suppressive potential under field conditions especially against diseases of French bean. The aim of this study was to investigate the suppressive potential of six composted substrates (farmyard manure, poultry manure, vermicompost, spent mushroom compost, Lantana camara and Urtica sp.), in comparison to a recommended chemical fungicide (carbendazim), against soil-borne and foliar diseases of French bean under the conditions of western Indian Himalayas. The field experiment was conducted over two growing seasons and the composts applied as a soil amendment and later as foliar sprays of their fermented extracts. There was a high level of root rot suppression (>33%) in the poultry manure, Lantana and Urtica compost treatments in both experimental years and these treatments were on par with the chemical seed treatment. All the compost treatments showed a moderate but significant reduction (>20%) in angular leaf spot severity also but none was comparable to that of chemical sprays. There was considerable variability in the suppressiveness of different composts. Overall, poultry manure, composted Urtica sp. and composted Lantana camara treatments were superior to other composts in suppressing both Rhizoctonia root rot ( Rhizoctonia solani Kuhn) and angular leaf spot ( Phaeoisariopsis griseola (Sacc.) Ferraris). The different compost treatments exerted a significant effect on the population of Trichoderma spp. and fluorescent pseudomonads in the plant rhizosphere. The highest population of these antagonists was recovered from poultry manure and Urtica compost treatments indicating that it may be a major factor contributing towards the higher disease reduction observed in these treatments. All composts increased yield over the control with maximum yields recorded in poultry manure and Urtica treatments. Although Lantana compost suppressed disease, the yield levels in this treatment were quite low indicating that the compost may be phytotoxic. Our results suggest that application of composts and compost extracts derived from poultry manure and Urtica sp. has the potential to provide effective control of diseases and improve yield in bean under field conditions.

Maize (Zea mays L.) is the third most important crop of country after rice and wheat and is cultivated round the year. Its grain is used as feed, food and industrial raw material. Enormous progress has been made during last six decades to enhance yield potential through genetic improvement and alleviate effects due to various biotic- and abiotic-stresses. This review presents an overview of strategies followed in genetic improvement of maize and assesses their impact on productivity and production of the crop. A diverse range of indigenous and exotic germplasm and breeding material have been utilized. Breeding programme has been very vibrant and various strategies viz., composite breeding, double cross, three way cross and single-cross hybrid breeding have been adopted in cultivar development to enhance productivity across a range of production ecologies. Since 2000, more than 165 high-yielding cultivars of different maturity periods and types [field corn, sweet corn, baby corn and quality protein maize] having adaptation to different agro-ecological zones have been released. Development of cultivars having tolerance to abiotic-stresses (water and temperature extremes) and resistance to diseases has been a priority area in maize improvement. Both conventional and molecular approaches have been and continue to be used in development of disease resistant, stress adapted and nutritionally superior cultivars. In order to realize full potential of improved cultivars, agronomic research has targeted several management interventions like plant density, mineral fertilization, water management, resource conservation and various maize-based cropping systems across different ecologies. Improved products have been delivered to farmers by both public and private sectors involved in maize seed production and distribution. As a result, area under improved cultivars has been increasing consistently, and currently approximately 65 % of maize area is under improved cultivars (mostly hybrids). Adoption of high-yielding cultivars, improved production technology and increased demand of maize resulted in increased production (from 1.7 to 24.4 million ton) and productivity (from 547 to 2583 kg/ha) from 1950–1951 to 2013–2014. Future prospects of maize cultivation and improvement strategies in context of climate change and in providing nutritional security are also discussed in this review.

Ten isolates of Fusarium spp. (F. proliferatum (4 isolates), F. verticillioides (5 isolates), and F. pallidoroseum (1 isolates) were collected from different parts of Rajasthan from rotted maize stalks and identified by ITCC, IARI (New Delhi, India). The maximum colony diameter (90mm), sporulation (3.4x105 X 3.8x105), size of macroconidia (40.24 X 6.60) and microconidia (10.33 X 1.50) and septation (5–7) were observed in isolate Fv-01 (F. verticillioides) whereas minimum colony diameter (54.70mm), sporulation (0.8 x105 X 1.6 x105), size of macroconidia (17.57 X 1.80) and microconidia (9.09 X 1.48) was observed in isolate Fv-09 (F. proliferatum). On the basis of cultural and morphological characters of all the ten isolates showed variability, but based on RAPD-PCR analysis, these isolates can be categorized into two major clusters I and II at 0.44% similarity coefficient. RAPD-PCR analysis suggested that variability was observed between species of Fusarium recovered from maize and the technique could be use to complement morphological characterization and to determine genetic relationships between the species.

Banded leaf and sheath blight incited by Rhizoctonia solani f. sp. sasakii Khunn. (Teleomorph: Thanatephorus cucumeris) is gaining devastating potentials in India. The pathogen is reported to show variation in expression of symptoms on the same genotypes grown in different locations. Fifteen isolates from trans-gangetic plains of India were collected to examine the cultural and morphological variability and pathogenic behaviour on host Zea mays. The isolates were from maize and rice host origins. Considerable variability was found among the isolates. The isolates of maize origin were poor sclerotia producing in culture, formed compact dense/fluffy, pale white to yellowish growth on PDA, producing irregular to organized, smooth surfaced sclerotia, faster radial growth in culture, acute branching of hyphae and high pathogenicity. The rice isolates showed a contrasting behaviour in forming sub-central to scattered, pitted sclerotia lighter in weight than maize counterparts, compact sparse colony, slow to medium radial growth, light brown to dark brown colony. Aerial bearing was not recorded in most of these isolates. All the rice isolates were fast sclerotia initiating in culture; however, higher incubation period was recorded in pathogenicity tests. The lesions were also scattered and disease score ranged from 2.6–3.1. The cultural and morphological parameters used in this investigation may be used to examine the biology of R. solani isolates from other agro-climatic regions also.