PATHOLOGICAL ASPECTS OF WILT AND ROOT ROT COMPLEX IN CHICKPEA (Cicer arietinum L.) AND THEIR MANAGEMENT 3653
dc.contributor.advisor | Dr. H. J. Kapadiya | |
dc.contributor.author | BHALIYA CHIRAGKUMAR MANSUKHBHAI | |
dc.contributor.other | 1010119030 | |
dc.date.accessioned | 2023-12-16T09:50:46Z | |
dc.date.available | 2023-12-16T09:50:46Z | |
dc.date.issued | 2023-02 | |
dc.description.abstract | Globally, pulses are considered as the second most common food source after cereal crops with high protein, vitamins and minerals content. The significance of pulses is much more in countries like India, where the majority of the people are vegetarians. Among the pulses, chickpea (Cicer arietinum L.) popularly known as bengal gram or chana is one of the important pulse crop grown in temperate, sub-tropical and tropical climate throughout the world. The several biotic and abiotic stresses become the prime reason for its low productivity. Among the different biotic stresses, wilt and root rot complex is considered the most important, devastating and challenging disease that becomes major limiting factor in successful cultivation of chickpea crop in Saurashtra region of Gujarat state. The management of chickpea wilt and root rot complex is quite difficult to achieve, as pathogens are soil borne in nature and survive in the soil for many years even in the absence of host by producing resistant structures i.e. chlamydospores and sclerotia. The effective control measures against this disease are not available till date. Considering the importance of this disease, the present investigation was performed to develop the most effective and eco-friendly management strategies to manage this soil borne complex disease. The pathogens can infect the crop at any stage of its growth. The disease characterized by shrinking of the collar region, drooping and chlorosis of petioles and leaves, internal discolouration of xylem vessels followed by rotting of tap roots with shredding of bark and lateral roots. The isolations were made from infected chickpea plant roots showing characteristic symptoms, revealed the association of Fusarium oxysporum f. sp. ciceri, Fusarium solani and Macrophomina phaseolina. Based on cultural and morphological characters, chickpea wilt and root rot complex pathogens were identified as F. oxysporum f. sp. ciceri, F. solani and M. phaseolina and further confirmed with molecular identification based on 18s rDNA ITS sequencing with NCBI accession number OP107270.1 (F. oxysporum f. sp. ciceri), OP102548.1 (F. solani) and OP094831.1 (M. phaseolina). The ITS rDNA region-based sequencing of M. phaseolina proved accurate for species-level identification of the pathogen, whereas Fusarium spp. were identified based on the multilocus analysis of the ITS region, TEF1-α and β-TUB gene. The phylogenetic trees were also constructed and compared with other similar worldwide fungal isolates available in the NCBI database. Out of sixty-five fungal isolates collected, thirty isolates of F. oxysporum f. sp. ciceri, twenty-five isolates of F. solani and ten isolates of M. phaseolina were observed that were designated as Foc, Fs and Mp, respectively. The frequency of occurrence of F. oxysporum f. sp. ciceri was high (46.15%) among all the samples collected followed by F. solani (38.46%) and M. phaseolina (15.39%). All the representative fungal pathogens isolated from infected plants were found pathogenic in pathogenicity test employed by soil and seed inoculation method. Abstract The survey was conducted to identify wilt and root rot complex hot spots and disease free areas in major chickpea growing tracts of Anand, Amreli, Bhavnagar, Jamnagar, Junagadh, Porbandar and Rajkot districts of Gujarat state. Out of ninety fields surveyed, eighteen fields were noted free from disease or near about negligible disease incidence (less than 5 per cent) whereas, seventy two fields were recorded as infected with the disease in a range of 1.25-52.78 per cent.The villages of Porbandar district viz, Madhavpur (52.78%), Kadegi (47.50%), Amipur (45.93%) and Ratia (40.65%) were identified as highly prone areas to wilt and root rot complex. The Fusarium spp. produce dense to sparse, fluffy to flat, white to pale yellow, pale violet, orange or pink colour colony with regular to irregular margin. It also produced hyaline, septate or aseptate, oval/ellipsoid to reniform/oblong, slightly curved/straight microconidia and 2-5 septate, sickle shape with pointed or blunt end macroconidia as well as globose/spherical to oval/pear, terminal or intercalary chlamydospores. M. phaseolina produced aerial, fluffy, compact, partial submerged, greyish white to blackish/brownish grey mycelium with spherical/circular to oval/oblong black microsclerotia. All the isolates of F. oxysporum f. sp. ciceri, F. solani and M. phaseolina exhibited tremendous variability in their cultural and morphological characters. The colonies of different isolates differed considerably with regard to their colony colour, texture, pigmentation and sporulation. The glaring differences in the size and shape of conidia/chlamydospore/sclerotia were also noticed among the isolates. The twelve isolates of F. solani and fifteen isolates of F. oxysporum f. sp. ciceri demonstrated the fast growth rate. Among 105 varieties/germplasm screened, none showed immune response against the wilt and root rot complex disease, whereas nine varieties/germplasm viz., WR-315 (6.26%), Phule G-08108 (6.33%), AKG-1303 (7.49%), JG 315 (7.89%), GJG 1713 (9.17%), GJG 2002 (9.44%), GJG 2015 (9.49%), GJG 1820 (9.69%), PUSA-256 (9.88%) were found as resistant, thirty seven were moderately resistant, thirty six were moderately susceptible, seventeen were susceptible and six were highly susceptible. The biochemical alteration in infected roots as compared to healthy roots revealed that sugar and protein content were maximum in healthy root of chickpea, while phenol content was maximum in infected root. The minimum decreased in protein (32.48%) and sugar (24.48%) content and maximum increase in phenol content (30.69%) was recorded in resistant germplasm (WR 315). Out of nine antagonists evaluated in vitro against wilt and root rot complex causing pathogens by dual culture technique, T. harzianum showed strongest antagonistic activity against F. oxysporum f. sp. ciceri (87.28%), while B. subtilis found to be the best antagonist against F. solani (84.62%). With respect to M. phaseolina, the maximum per cent growth inhibition was observed in T. virens (70.98%). In field condition, seed biopriming treatment for 10 hrs with the suspension of talc-based formulation of B. subtilis (1x108 CFU/g) @ 50 g in 250 ml of water/kg of seed remained the best treatment with minimum disease incidence (4.79%), maximum seed yield (2339 kg/ha), seed germination (97.10%), root (12.62 cm) and shoot (25.05 cm) length as well as vigour index (3021). The chickpea wilt and root rot complex disease was effectively managed under irrigated field conditions by soil application of B. subtilis (1x108 CFU/g) @ 5 kg/ha enriched in 500 kg FYM/ha as it recorded minimum disease incidence (15.24%) and highest seed germination (96.55%) and seed yield (2228 kg/ha). While, soil application of T. harzianum (2x106 cfu/g) @ 5 kg/ha enriched in 500 kg FYM/ha was found most effective under unirrigated field condition with 96.87 per cent seed germination, 7.60 per cent disease incidence and 1383 kg/ha seed yield. | |
dc.identifier.uri | https://krishikosh.egranth.ac.in/handle/1/5810203579 | |
dc.language.iso | English | |
dc.pages | 267 | |
dc.publisher | JAU JUNAGADH | |
dc.relation.ispartofseries | 3653 | |
dc.sub | Plant Pathology | |
dc.theme | PATHOLOGICAL ASPECTS OF WILT AND ROOT ROT COMPLEX IN CHICKPEA (Cicer arietinum L.) AND THEIR MANAGEMENT 3653 | |
dc.these.type | Ph.d | |
dc.title | PATHOLOGICAL ASPECTS OF WILT AND ROOT ROT COMPLEX IN CHICKPEA (Cicer arietinum L.) AND THEIR MANAGEMENT 3653 | |
dc.type | Thesis |