A survey was conducted on aromatic rice during the kharif seasons of 2019 and 2020 in the five valley districts of Kakching, Thoubal, Bishnupur, Imphal-East, and Imphal-West, Manipur to assess the natural disease occurrence of blast, brown spot and sheath blight diseases. The survey revealed that disease incidence and severity varied with locations. Blast, brown spot, and sheath blight have an overall disease incidence of 36.94

The widespread occurrence and predominant association of chilli veinal mottle virus (ChiVMV) with the valuable chilli landraces of North East Region (NER) of India and associated threat to chilli production necessitated the development of simplified and robust detection procedure. Present study reports a simplified reverse transcription-recombinase polymerase amplification (RT-RPA) method for detection of ChiVMV in crude leaf extract prepared through simplified extraction protocol using NaOH:EDTA (1:1) based tissue lysis, without the need of conventional RNA extraction and sample processing. Developed RT-RPA assay could be performed at an isothermal temperature (38 degrees C) in 30 min and exhibited no cross-reactivity with other prevalent chilli viruses (potato virus Y, cucumber mosaic virus, large cardamom chirke virus, capsicum chlorosis orthotospovirus, pepper mild mottle virus and chilli leaf curl virus), indicating high specificity. It could detect ChiVMV up to 10-9 dilution (100 ag/mu l) of crude leaf extract, 10 ag/mu l of RNA of ChiVMV infected leaf tissues and plasmid DNA containing viral gene insert, thus exhibiting sufficient sensitivity which is at par or better than the standard RT-PCR. Developed RT-RPA assay was employed to reveal the widespread occurrence of ChiVMV in NER India with 50.81% (1545 samples tested) of symptomatic and 7.85% (1593 samples tested) of asymptomatic samples tested positive. RT-RPA exhibited higher sensitivity in detection of ChiVMV infection in field samples as compared to the standard RT-PCR which gave false negative in 2.07% of symptomatic and 2.01% of asymptomatic samples. The developed assay was further applied in screening of 49 chilli germplasm for ChiVMV infection. The pooled results of field screening based on the disease score indicated that none of the chilli germplasm had immune or complete resistance, while 29 chilli germplasm (bird's eye chilli: C. frutescens; Morokatekpa: C. annuum, Leihao morok, Morok masingkha; Chingpimorok: Capsicum sp.) exhibited tolerant reaction with a disease score of 1.27-2.00. All the tested bird's eye chilli germplasm showed tolerance to the ChiVMV. The artificial screening to the severe isolate and qRT-PCR based viral titre determination confirmed the results of field screening wherein the germplasm RCMC6, RCMC7, RCMC17, RCMC27 and RCMC42 exhibited either asymptomatic or mild mosaic symptoms and decrease in viral titre at 20 DAI thus categorized as tolerant. The simplified RT-RPA assay developed and validated in the present study can be applied in routine detection of ChiVMV in field samples, disease-free seedling production and resistance screening under resource poor laboratory setup with limited technical expertise. Chilli germplasm with tolerance to ChiVMV identified in the present study can be used as donors in resistance breeding.

Ten cultural media, namely Potato sucrose agar (PSA) medium, Potato dextrose agar (PDA) medium, Czapek’s dox agar medium, Corn starch agar medium, Oat meal agar (OMA) medium, Rice straw agar medium, Rice grain agar medium, Rice leaf extract agar medium, Malt extract agar medium, and V8 juice agar medium, were used to observe the growth of three fungal pathogens of aromatic rice, viz., Pyricularia oryzae, Bipolaris oryzae, and Rhizoctonia solani. The radial growth and colony characteristics were greatly influenced by the medium used. In a comparative study of the higher mycelial growth of the three test fungi at ten different mediums, the best performance was observed in rice straw medium (Pyricularia oryzae and Bipolaris oryzae) and in rice leaf agar medium (Rhizoctonia solani). These results will find use in further fungal taxonomic in vitro studies.

An experiment was conducted in vitro to evaluate the antagonistic potential of six native Trichoderma species viz., T. ovalisporum (KU904456), T. harzianum (KU933468), T. atroviride (KU933472), T. harzianum (KU933474), T. asperellum (KU933475), T. koningiopsis (KU904460) against Alternaria solani (Ellis and Martin) causing early blight of potato through dual culture technique. Six native Trichoderma species were tested, and NCIPMCAU-69 (T. harzianum), which was found to be the most effective and recorded significantly higher mycelial growth suppression of A. solani by 71.37% followed by NCIPMCAU-131 (T. harzianum) by 70.98%, NCIPMCAU-96 (T. ovalisporum) by 69.80%, NCIPMCAU-18 (T. koningiopsis) by 69.02% and NCIPMCAU-118 (T. atroviride) by 68.62% respectively. The growth of A. solani was significantly suppressed by all native species of Trichoderma. The results indicate the ability of Trichoderma species as potential antagonists and capable of reducing the growth of A. solani causing early blight of potato.

Rice is cultivated and consumed worldwide being a cereal crop of chief importance. There are numerous soil-borne fungi causing diseases of huge economic losses to production of rice. A survey of soil-borne fungi of rice was conducted in different valley districts of Manipur, and symptoms appearing as lesions, water-soaked spots near the waterline which often coalesces, forming concentric lesion bands were spotted. Among the collected symptomatic samples, a fungus, Ceratorhiza oryzae - sativae was identified. An internal transcribed sequence of the isolated fungus was generated and an NCBI accession number, MH255604 acquired. This disease might become severe in near future in all rice-growing fields of the state, and identification of this pathogen shall be essential for developing the management strategies.

Chilli veinal mottle virus (ChiVMV), a potyvirus has emerged as the most devastating threat to chilli cultivation in North East Region (NER) of India. Its wide prevalence and higher rate of transmission led to crippling of chilli groves, especially of landrace U-morok (C. chinense) in NER of India. Current study elucidates widespread occurrence of ChiVMV, its association with varied symptoms of U-morok and the genetic diversity from Manipur state of NER India. A total of 1241 chilli leaf samples were collected during 2019–2021 from the 42 major U-morok groves exhibiting diverse symptoms of mild to severe decline. Molecular detection using standard reverse transcription polymerase chain reaction (RT-PCR) by employing the ChiVMV specific primers targeting coat protein (CP) and 3′-UTR (3′-untranslated region) genomic region of ChiVMV genome showed that out of a total of 1241 U-morok samples, 788 samples (63.50

Trichoderma is a free living fungi which are highly interactive in root, soil and foliar environments as well. Trichoderma can be used as a biological control agent due to its ability such asmycoparasitism, production of antibiotic and/or hydrolytic enzymes, competition for nutrients, as well as induced plant resistance; production of numerous secondary metabolites inhibitory to the growth of several plant pathogens. In this study, the antagonistic potential of some native rice specific Trichoderma isolates were evaluated against sheath blight disease of rice caused by Rhizoctonia solani. It revealed that the inhibition percentages of R. solani by the native rice specific Trichoderma isolated from various soil samples of Manipur ranges from 62.50% to 87.50% with highest per cent inhibition by WAI-D,T. harzianum (MH257323), and lowest by LAM-B,T. brevicompactum (MH257322) of 87.50% and 62.50% respectively. Bell’s scale study showed class III category by T. brevicompactum (MH257322) and class II showed by T. harzianum (MH257323) against Rhizoctonia solani. Among the native rice specific Trichoderma isolates, WAI-D, T. harzianum (MH257323) is found to be the most effective in reducing the rapid growth of pathogen. Further, all native Trichoderma isolates significantly inhibited the mycelial growth of the pathogen.

The present study was designed to evaluate the antifungal effect of six different fungicides viz., Carbendazim, Copper oxychloride, Captan, Thiophanate methyl, Ridomil, and Carboxin + Thiram. The evaluation was carried out at different concentrations i.e., 0.025%, 0.05%, 0.1%, 0.2% and 0.4% against mycelial growth of Fusarium oxysporum f.sp. pisi (FOC) by “poisoned food technique”. Results obtained on in vitro evaluation revealed that all the test concentrations of all fungicides significantly inhibited growth of (FOC) as compared to control. It was observed that the pathogen could not grow at all different concentrations viz., 0.025%, 0.05%, 0.1% and 0.2% in Carbendazim, yielded 100 per cent inhibition of mycelial growth of the pathogen and least inhibition was observed with Copper oxychloride (1.15 per cent) at 0.05% concentration. On the basis of available information and preliminary study, it is suggested that Carbendazim can be used in the management of Fusarium wilt of pea.

A detailed survey was conducted for disease incidence of pea wilt at seven pea growing districts of Manipur viz., Imphal East, Imphal West, Thoubal, Senapati, Ukhrul, Tamenglong and Bishnupur during 2014-2015.The highest disease incidence was found in Litan of Ukhrul district (39.50%) and lowest was found at Toubul of Bishnupur district (10.70%).Under pot experiment, efficacy of four native Trichoderma isolates i.e., TIE-1 TBI-2, TIW-1, TSE-1 and two commercial Trichodema spp.viz T. viride and T. hamatum of seed, soil and seed plus soil treatment against wilt of pea showed reduction in disease incidence.Among the different treatments seed+soil treatment was found better than the soil and seed treatment alone.The highest germination percentage was observed in isolate TIE-1 of seed (60%), soil (66.60%) and seed+soil treatment (80.20%) and lowest germination percentage was observed in commercial T. hamatum of seed (53.60%), soil (60.00%) and seed+soil treatment (65.00%).Disease incidence of four native Trichoderma isolates and two commercial Trichoderma were found nil in 30 DAS.In 60 DAS the highest disease incidence was found in commercial T. hamatum in seed treatment (20.00%) and lowest disease incidence was found in native Trichoderma TSE-1 of seed+soil treatment (2.50%) whereas in 90 DAS highest disease incidence was also found in T. hamatum in soil treatment (40.00%) and lowest disease incidence was found in native Trichoderma isolate TIE-1 of seed+soil treatment (10.66%).The highest plant height was recorded in seed+soil treatment of isolate TBI-2 (70.28 cm at 90 DAS).However in seed+soil treatment of Trichoderma isolate TIE-1 recorded the highest plant canopy (2085.03cm 2 at 90 DAS) no. of pods plant -1 (5.34) and yield (6.91 g pot -1 ).Modern agriculture is very much dependent on the use of chemical pesticides to control plant pathogens in which the repeated use of such chemicals increased resistance among the target organisms.Therefore, management of plant pathogens by using biocontrol agents has been considered as a potential control strategy in recent years.Trichoderma sp. is one of the most important biocontrol agent used for management of different diseases (Harman, 2004).Trichoderma spp.are free living fungi that are common in soil and root ecosystems and promote plant growth (Yedidia, I and Chet, I. (2001).Trichoderma spp.

Rice seeds were bio primed with native Trichoderma isolates for their efficacy of biocontrol and enhancing seedling vigour of the plant. In the investigation fifteen treatments were carried out using native Trichoderma isolates including the control. Among the fifteen treatments tested including the control, the treatment of T. harzianum isolate WAI-D has shown the best performance giving highest seed germination of 92.00 per cent and seedling vigour index of 944.84 which was statistically superior over other treatments and nonetheless Trichoderma viride isolate CHK-I has shown good performance which comes next to the best with germination percentage of 86.33 and seedling vigour index of 661.28 and the least per cent seed germination were observed in the control. The difference in results observed may be due to the presence of variable level of enzymatic activity of the different isolates of native Trichoderma isolates and also the difference in the ease of substantial multiplication of the biocontrol agents on seed in the process of bio priming.

Mungbean Yellow Mosaic Virus (MYMV), a whitefly transmitted Gemini virus, is one of the severe constraints that afflict blackgram crop in India and other countries. Mungbean yellow mosaic disease incidence ranged between 3.73 (DKU-87) and 96.15% (LBG-623). Based on disease reactions, nine genotypes i.e., DKU-87, DKU-102, KPU-21, UG-281, KPU-6, KPU-29, KPU 12-1731, KPU 12-133 and PU 12-11 were categorized as resistant (0.85 to 1.50 score), while LBG-752 as moderately resistant (2.75) and genotypes OBG-32, KPU-1, KPU-22 and KPU-9 as susceptible whereas Co5 and LBG-623 as highly susceptible. Whitefly infestation was first noticed by 14 day after sowing and its population gradually increased till 70 DAS, which declined later with slight fluctuations in all genotypes. The highest whitefly population per plant was recorded in LBG-623 (7.55) which was followed by Co5 (7.34). A positive correlation (0.973) was observed between whitefly population and MYMV severity.

The genetic variability of 'Candidatus Liberibacter asiaticus' (CLas) population associated with huanglongbing (HLB) disease of citrus in North Eastern (NE) region of India, a geographically locked region, and home for the diversity of many citrus species was analyzed on the basis of tandem repeat numbers (TRN) in variable CLIBASIA_01645 genomic loci. Fifty-five CLas strains sampled from different groves of NE Hill (NEH) region of India were in single amplicon group, but there was remarkable genetic variability in TRNs. The TRN in HLB-associated CLas strains varied from 0-21 and two novel repeat motifs were also identified. Among the NE population of CLas, TRN5 and TRN9 were most frequent (total frequency of 36.36%) followed by TRN4 (14.55%) and TRN6, TNR7 with a frequency of 12.73% each. Class II type CLas genotypes (5 < TRN ≤ 10) had highest prevalence (frequency of 60.00%) in the samples characterized in present study. Class I (TRN ≤ 5) genotypes were second highest prevalent (29.09%) in the NEH region. Further analysis of genetic diversity parameters using Nei's measure (H value) indicated wide genetic diversity in the CLas strains of NE India (H value of 0.58-0.86). Manipur CLas strains had highest genetic variability (0.86) as compared to Eastern, Southern and Central India. The R10 values (TRN ≤ 10/TRN > 10) of NE CLas population was 10.43 (73/7), higher from other regions of India. Present study conclusively reported the occurrence of high genetic variability in TRN of CLas population in North East Indian citrus groves which have evolved to adapt to the specific ecological niche.

Present research was carried out to understand antagonistic potentiality of six native Trichoderma spp. against Rhizoctonia oryzae-sativae causing Aggregate sheath spot of rice. Dual culture technique revealed the inhibition percentages of R. oryzae-sativae by T. asperellum (KU933475), T. koningiopsis (KU904460), Hypocrea lixii (KX0113223), T. harzianum (KU904458), T. ovalisporum (KU904456) and T. atroviridae (KU933472) of 58.43%, 68.23%, 60.0%, 72.94%, 64.31%, and 70.19% respectively. Bell’s scale study showed class III category by Trichoderma spp and class II showed by T. harzianum (KU904458) against Rhizoctonia oryzae-sativae. Among the different biological agents Trichoderma harzianum is the most effective one for reducing rapid growth of the pathogen. Further, all Trichoderma isolates significantly inhibited the mycelial growth of the pathogen.

Huanglongbing (HLB), also known as the “greening disease” is a serious disease affecting major citrus growing groves in India as well as in the world. The presumptive causal agent is a fastidious, gram negative, α- subdivision of the proteobacteria named Candidatus Liberibacter asiaticus (CLas) transmitted by Asian citrus psylla (Diaphorina citri). Different symptoms varying from yellowing of leaves, whole branch (called yellow shoot disease in China),drying of twigs, yellow patches in newly emerged flushes, irregular patches of yellowing on leaves (blotchy mottle), rabbit ear like appearance of leave and mineral deficiency like symptoms (leave showing symmetrical pattern of chlorosis on both sides of mid rib) were mainly observed on different citrus species during the survey conducted at various citrus growing pockets of Manipur in the present study. The leaves of citrus tree exhibiting the symptoms akin to mineral deficiency and rabbit ear like appearance were tested positive for HLB infection. Out of total 40 samples tested from different parts of Manipur by normal conventional PCR using specific primer targeting partial 16S rDNA, 19 samples were tested positive (47.50% infection) indicating high prevalence of HLB in different parts of Manipur. Highest percent infection of HLB was observed in Kachai Village, Ukhrul district, Manipur (72.72%) followed by Noney region of Tamenglong District (50%of tested samples were positive) and lowest incidence was recorded from Imphal West and East districts of Manipur (33.33%of tested samples were positive). These findings indicated widespread prevalence of HLB in different citrus growing pockets of Manipur.

Pea (Pisum sativum L.) is native of South Europe and gown a garden or field crop throughout the temperate regions of the world and was originally cultivated in the Mediterranean basin (Smartt, 1990; Sardana et al., 2007). In India, pea is one of the most important rabi pulse crops, in which the crop is grown on a field scale for its dry seeds and smaller scale for green peas. Peas being very rich in protein are valuable for vegetable purpose. It is rich source of protein, amino acid, sugar, carbohydrates, vitamins A and C, calcium and phosphorus besides having a small quantity of iron.

ISSN: 2319-7706 Volume 7 Number 07 (2018) Journal homepage: http://www.ijcmas.com Stem-end rot of mango caused by Lasiodiplodia theobromae and Lasiodiplodia pseudotheobromae is a major post-harvest problem in Manipur and reduces yield. An experiment on antifungal efficacy of three plant extracts viz., Garlic (Allium sativum), Neem (Azadirachta indica) and Ginger (Zingiber officinale) was done through poisoned food technique by taking three concentrations in in vitro conditions against the pathogens and eight Trichoderma isolates viz., T. ovalisporum (KU904456), T. koningiopsis (KU904460), T. harzianum (KU904458), T. atroviride (KU933472), T. harzianum (KU933474), T. asperellum (KU933475), T. asperellum KU933476) and T. hypocrea (KX0113223) were evaluated against the pathogens through production of non-volatile (Dennis and Webster, 1971a) and volatile Dennis and Webster, 1971b) compounds. The results revealed that among plant extracts, the highest inhibition for Lasiodiplodia theobromae was shown by garlic at 1.25, 2.5 and 5 per cent of 100 per cent and for Lasiodiplodia pseudotheobromae, the highest inhibition was showed by garlic at 5 per cent of 81.17 per cent. Effect of volatile compounds produced by Trichoderma spp against Lasiodiplodia theobromae showed maximum percentage inhibition with isolate T. asperellum (KU933476) of 95.24 per cent and T. hypocrea (KX0113223) least by 68.52 per cent. Effect of volatile compounds produced by Trichoderma spp against Lasiodiplodia pseudotheobromae showed maximum percentage inhibition with isolate T. ovalisporum (KU904456) of 12.39 per cent and no inhibition was observed by T. asperellum (KU933475), T. atroviride (KU933472), T. harzianum (KU933474), T. harzianum (KU933458), T.koningiopsis (KU904460), and T. hypocrea (KX0113223) against the pathogen. Effect on non-volatile compounds produced by Trichoderma spp. at two different concentrations viz., 7.5% (v/v) and 15% (v/v) against Lasiodiplodia theobromae showed 42.36 to 82.40 per cent at 7.5% v/v concentration and 53.70 to 100.00 per cent at 15% v/v concentration, In Lasiodiplodia pseudotheobromae, results showed 3.59 to 56.31 per cent at 7.5% v/v concentration and 44.47 to 100.00 per cent at 15% v/v concentration. Present study suggests that Garlic and Trichoderma spp. could be tried for the eco-friendly management of the diseases. K e y w o r d s Mango, Postharvest, Plant extracts, Trichoderma spp Accepted: 06 June 2018 Available Online: 10 July 2018 Article Info Int.J.Curr.Microbiol.App.Sci (2018) 7(7): 448-457

Sclerotium rolfsii is a soil inhabitant, non-target, polyphagous, and a ubiquitous facultative parasite. Its geographic distribution, profuse mycelial growth, persistent sclerotia and large number of hosts attacked by it indicate that, economic losses are substantial every year due to infection. The present study was carried out to understand about the in vitro efficacy of some agrochemicals (Fungicides- difenconazole, propiconazole and hexaconazole, Herbicides - paraquat, glyphosate and pendimethalin and Insecticides - imidachloprid, fipronil and chlorpyriphos) with three different concentrations for each chemical on radial growth of the fungus. It is observed that among the fungicides hexaconazole had showed 100percent inhibition at 12.5ppm, herbicide pendimethalin (0.4%) and insecticide chlorpyriphos (0.125%) respectively.

Anthracnose of chilli caused by Colletotrichum capsici is a widespread problem limiting the profitable cultivation of chilli in Manipur. An experiment on antifungal efficacy of four plant extracts viz., Garlic (Allium sativum), Neem (Azadirachta indica), Citronella (Cymbopogon spp), Ginger (Zingiber officinale) and three Cow urine, Cow dung, Cow milk viz., Cow urine, Cow dung, Cow milk and honey was done through poisoned food technique by setting three concentrations in in vitro conditions against C. capsici. The results revealed that among the plant extracts, garlic had shown 70.19 per cent inhibition at 5 per cent concentration and among the Cow urine, Cow dung, Cow milk and honey, cow milk had shown 69.80 per cent inhibition at 15 per cent concentration. Present study suggests that Garlic and cow milk could be tried for the eco-friendly management of the disease. Citronella extract and cow dung found to be less effective.

Different agar media, including natural, Oat Meal Agar (OMA), Malt Extract Agar (MEA), V8 Agar and Leaf extract agar of host plant, semi-synthetic media, Potato Dextrose Agar (PDA), carrot dextrose agar (CaDA) and synthetic media, Czapex Dox Agar (CDA), Richards Synthetic Agar (RSA), Asthana and Hawkers Agar (AHA)) were used to observed the mycelial growth rate, cultural and morphological characters of four fungal isolates after seven days of incubation at 26±1°C. The colony character including diameter, culture characteristics (texture, surface and reverse colouration, zonation) and sporulation of selected test fungi were greatly influenced by the type of growth medium used. On comparative study of higher mycelial growth of the four test fungi, the best performance where observed in PDA as well as moderate to heavy sporulation on this culture medium. These results will find use in fungal taxonomic studies.