Yellow Mite Research Articles

Field Evaluation of Sugarcane Varieties Against Yellow Mite Oligonychus sacchari McGregor (Prostigmata: Tetranychidae)

Sugarcane yellow mite, Oligonychus sacchari (Prostigmata: Tetranychidae), is one of the main detrimental pests in sugarcane growing areas in Iran. The early populations of mites colonize on the lower surfaces of sugarcane leaves. Because of high reproductive potential, multi-generation are produced per year under warm and humid temperature during sugarcane growing season. This pest imposes economic damage to sugar industries. Field trials were conducted on evaluation of varietal resistance of five sugarcane varieties against yellow mite during two successive seasons 2014–2015 and 2015–2016 in sugarcane fields at Salman Farsi Agro-industry unit in Ahwaz, Iran. After initiation of O. sacchari activity in fields, in each plot, fifteen leaves were selected at random and number of living mites was recorded. The results showed that there were significant differences among tested varieties. The variety IRC99-02 was the most susceptible in tested years by CP57-614 in the total number of living mites and dry-leaf even though CP69-1062 was the most resistant variety.

Studies on genetic variability and screening for fibre yield components and biotic stress factors in tossa jute (Corchorus olitorius L.) germplasm under Terai region of West Bengal

A study was carried out with 75 germplasm accessions along with two checks (JRO-524 and JRO-204) of tossa jute (Corchorus olitorius L.), over two years (2013 and 2014) at Instructional Farm of Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal, India, for eight characters, out of which four were fibre yield components (plant height, basal diameter, green weight and fibre yield) and the remaining four were biotic stress components (incidence of yellow mite, semi looper, stem rot and root rot), affecting the fibre yield. The germplasm accessions differed significantly for plant height, fibre yield, the incidence of yellow mite, semi looper and stem rot. The highest fibre yielding accession was OIN-142 (17.15 g/plant) which performed significantly better than the two checks. The mean fibre yield of all the genotypes indicated that the fibre yield loss was more due to the incidence of stem rot and root rot rather than yellow mite and semi looper. The germplasm accession OIN-06, OIN-15, OIN-03, OIN-17, OIN-01, OIN-617, OIN-559 and OEX-09 were found to be tolerant towards stem rot incidence and the root rot incidence was low in OIN-93, OIN-86, OIN-25 and OIN-60. The genotypes were distributed in 12 clusters as per D2 analysis, out of which cluster-XII had the highest number of genotypes (40) followed by cluster-III (10) and cluster-I (9). The remaining 9 clusters had 2 genotypes each. The highest inter-cluster D2 value was found between cluster-III and cluster-IV (33.99) and the highest intra-cluster D2 value was found in cluster-I (35.90). The contribution to total divergence was higher by the four biotic factors namely yellow mite, semi looper, stem rot and root rot as compared to the fibre yield components. The greater difference between the GCV and PCV for the eight characters under study revealed the major role played by the environment in the expression of these characters which were further substantiated by the low heritability and genetic advance of the characters. Among the biotic factors, stem rot and root rot were found to decrease fibre yield significantly with increase in their incidence level. It was the negative association of stem rot and root rot with plant height which was the deciding factor in reducing the fibre yield drastically. On screening of the germplasm accessions by giving proper weightage to tolerance, higher fibre yield and genetic divergence, it was found that the genotypes OIN-03, OIN-06, OIN-15 and OIN-17 in cluster-I and the genotypes OIN-86 and OIN-93 in cluster-XII may be used in a hybridization programme, to enhance fibre yield along with tolerance to the two major biotic stress components, namely stem rot and root rot.

Biological control of yellow mite Polyphagotarsonemus latus on Capsicum chinense

A study on the biological control of yellow mite Polyphagotarsonemus latus in hotchilli, Capsicum chinense was carried out in the Acarology laboratory, and under field conditions at the Department of Entomology, Assam Agricultural University, Jorhat during 2014 and 2015. The predatory mite Amblyseius cucumeris as biocontrol agent was evaluated. Under laboratory conditions, there was maximum reduction of yellow mite with 1: 12 predator-prey ratio, while there was least reduction with 1: 33 ratio. Under field conditions, A. cucumeris release @5, 6, 7, 8, 9 and 10 predators/leaf resulted in significant control, with highest reduction being achieved with release of 10 predators/leaf i.e., 56. 95, 83.06, 100 and 100% after 3, 6, 9 and 12 days of release, respectively. The predatory mite A. cucumeris was found to be thus effective in controlling the yellow mite even at low pest density under field condition.

In vitro Toxicity assessment of synthetic acaricides against yellow mite, Polyphagotarsonemus latus (Banks), and predatory mite, Amblyseius ovalis (Evans), on chilli plants

<i>In vitro</i> Toxicity assessment of synthetic acaricides against yellow mite, <i>Polyphagotarsonemus latus</i> (Banks), and predatory mite, <i>Amblyseius ovalis</i> (Evans), on chilli plants

The toxicity of Biomite ® , GC-mite ® , Oberon ® and Envidor ® acaricides against sugarcane yellow mite, Oligonychus sacchari (Acari: Tetranychidae)

The sugarcane yellow mite, Oligonychus sacchari (McGregor, 1942) is one of the most important pests of sugarcane. In this study, the acaricidal efficacy of four different acaricides including Biomite ® , GC-mite ® , Oberon ® and Envidor ® was assessed under laboratory conditions at 28 ± 0.5oC, 50 ± 5% RH and a photoperiod of 16:8 h (L:D). Adults of O. sacchari were exposed to treated leaves of sugarcane, CP57-614 variety and the mortality was counted after 24 and 48 h of exposure. Results indicated that for Biomite ® the concentration of 1.5 lit/ha and in the case of GC-mite ® , 1 lit/ha was more effective against O. sacchari . There were no significant differences between the Oberon ® and Envidor ® after 24 h of exposure. However, the toxicity of Oberon ® increased after 48 h time interval. LC 50 values of Biomite ® , GC-mite ® , Oberon ® and Envidor ® were 1.01, 0.86, 0.99 and 1.73 lit/ha, respectively. Application of acaricides can be effective tool for the control sugarcane yellow mite and it can be integrated with other control techniques.

Efficacy of three botanicals and a microbial derivatives acaricide (Abamectin) on the control of jute yellow mite, Polyphagotarsonemus latus (Bank)

Three botanical oils and of microbial derivatives an acaricide (Abamectin) were evaluated for their efficacy in controlling yellow mite Polyphagotarsonemus latus in the field laboratory of Entomology, Bangladesh Agricultural University, Mymensingh. The selected botanical oils viz. Neem oil, Mahogany oil and Karanja oil and the acaricide Ambush 1.8 EC were tested against jute yellow mite on standing jute plants of the experimental plots and assessed for their effect on the basis of population of the pest at 24, 48 and 72 hours after treatment and the reduction of yellow mite infested plant after 7 and 10 days of spraying. The acaricide Ambush 1.8 EC was highly effective showing reduction of 80.25% mite infested plant. Among the botanicals, Neem oil and Mahogany oil showed better efficacy and caused 60.55 % and 55.89 % reduction of mite infestation. Karanja oil was not found promising in controlling yellow mite of jute. Considering the effectiveness against the mite pest as well as the environmental safety, use of Neem and Mahogany oil and also the reduced risk acaricide, Ambush 1.8 EC might be suggested in the IPM of yellow mite.J. Bangladesh Agril. Univ. 14(1): 1-6, June 2016

Incidence and population builds up of P. lotus infesting Capsicum chinense Jacq. in relation to weather factors

An Experiment was conducted in the experimental plot, Department of Entomology, Assam Agricultural University, Jorhat during 2014 and 2015 to study the population build up of P. lotus infesting Capsicum chinense with respect to weather factors. In the present investigation, the highest population (no/leaf) of yellow mite, P. latus was observed in the month of March with maximum 45 and 28 number of yellow mite per leaf in 2014 and 2015, respectively. The highest overall per cent incidence recorded was 80.61 in the last week of March whereas lowest overall incidence was found in May with 20.12 per cent mite incidence The correlation studies between P. latus and weather parameters revealed that population build up of P. latus found to be significant negative correlation with morning relative humidity (r=-0.787 and r=-721) and rainfall (r=-0.526) in both the years, respectively. Maximum temperature, minimum temperature and evening relative humidity showed a negative and non- significant correlation with mite population. Bright sunshine hour was found to be positively correlated. This present findings will certainly be a helpful for yellow mite forecasting as well as management point of view and to have profitable cultivation of Capsicum chinense by way of mite free crop production.

Impact of different pest management modules against the major sucking pests complex of chilli (Capsicum annuum)

Three different pest management modules were tested against major sucking pests complex of chilli (Capsicum annuum L.) (thrips, yellow mites) and occurrence of Pepper leaf curl virus transmitted by whitefly [Bemisia tabaci (Gem.)] and compared with the untreated control. Two promising varieties (Kashi Anmol and Kashi Gaurav) were sown at experimental plots of IIVR and three pest management modules, viz. biointensive module (M1), integrated module (M2) and chemical module (M3) were examined for two consecutive years (2011-12 and 2012-13). All the tested modules were found significantly applicable over the control in terms of pest and disease management. Among these, integrated module (M2) comprising seedling dip with Imidacloprid 17.8% SL@ 1 ml/ l of water, spraying of Buprofezin 25%SC @ 1 ml/l at 25 DAT, Fipronil 5% SC@ 2 ml/l at 35 DAT, Lecanicillium (=Verticillium) lecanii @ 5 g/l at 45 DAT, Chlorfenapyr 10% SC@ 1.5 ml/l at 55 DAT, neem oil 1% at 65 DAT and their need based rotation was most effective in reducing the thrips and mite population in chilli and significantly enhancing the yield over control. Reduced yellow mite population was observed in both the varieties, i.e. Kashi Anmol (79.16%) and Kashi Gaurav (73.59%). Likewise, reduction in thrips population was also recorded in Kashi Anmol (58.09%) and in Kashi Gaurav (48.16%) varieties. However, occurrence of Pepper leaf curl virus was lowest in chemical module (M3), viz. 7.04% and 11.18% lower leaf curl infestation was observed, respectively in Kashi Anmol and Kashi Gaurav varieties followed by integrated module (M2) with 8.36% and 12.64% less leaf curl infestation. In terms of cost benefit ratio, integrated module (M2) was found applicable for both the varieties, i.e. 1:2.26 and 1:6.66 cost benefit ratios were recorded respectively in Kashi Anmol and Kashi Gaurav. Thus, integrated module (M2) may be adopted to get rid of these sucking pests menace.

MANAGEMENT OF SUCKING PESTS, BY INTEGRATION OF ORGANIC SOURCES OF AMENDMENTS AND FOLIAR APPLICATION OF ENTOMOPATHOGENIC FUNGI ON CHILLI

A field experiment was conducted to evaluate the efficacy of different organic amendments viz., farm yard manure (FYM), neem cake (NC) and Pseudomonas fluorescens in combination with certain entomopathogenic fungal formulations viz., Hirsutella thompsonii Fisher, Beauveria bassiana (Balsamo), and Lecanicillium lecanii (Zimm.) against sucking pests of chilli viz., aphids, Myzus persicae (Sulzer), chilli thrips, Scirtothrips dorsalis Hood and muranai mite, Polyphagotarsonemus latus (Banks). Among fourteen treatments tested, seed treatment with P. fluorescens @10 g kg-1 of seed + foliar application of B. bassiana @ 1x108 CFU ml-1, neem cake @ 600 kg ha-1 + B. bassiana @ 1x108 CFU ml-1 and farm yard manure @ 12.5 t ha-1 + B. bassiana @ 1x108 CFU ml-1 were found promising against sucking pests of chilli, which are statistically on par. The next effective treatment was P. fluorescens @ 10 g kg-1 of seed + L. lecani @ 1 x 10-8 CFU ml-1 in reducing population of aphids and thrips on chilli, With regard to yellow mite of chilli, P. fluorescens @ 10g kg-1 of seed + H. thompsonii @ 1 x 10-8 CFU ml-1 was found effective. Further, treatment combination of organic amendments with formulations of B. bassiana recorded highest yield of green chillies and cost benefit ratio (CBR).

Evaluation and dosage standardization of novel molecule, Cyenopyrafen 30% SC against yellow mite (Polyphagotarsonemus latus) in chilli (Capsicum annuum)

Field trials were carried out at the Institute of Pesticide Formulation Technology, Gurgaon, Haryana, India during kharif 2013 and 2014 to evaluate the field efficacy and to fix the correct dose of novel molecule cyenopyrafen 30% SC for the management of the yellow mite [Polyphagotarsonemus latus (Banks)] infesting chilli (Capsicum annuum L.). The chemical cyenopyrafen 30% SC was evaluated @ 150, 200, 250 and 300 ml/ha along with fenpyroximate 5% EC and propargite 57% EC @ 600 and 1500 ml/ha, respectively. The results revealed that at 14 days after spraying (DAS), the chemical treatments, cyenopyrafen 30% SC @ 200ml/ha and fenpyroximate 5% EC emerged significantly the best with record of 1.56 to 2.18 mites/leaf and registering 84.36 to 89.15% reduction over untreated control (13.46 mites/ leaf) at 10 DAS. Other doses of cyenopyrafen 30% SC @ 200 and 250 ml/ha were on par with the higher dose @ 300 ml/ha and fenpyroximate 5%EC @ 600 ml/ha. Significantly highest marketable fruit yield was recorded in the higher doses of cyenopyrafen 30% SC treatments, i.e. @ 200, 250 and 300 ml/ha (26.05 to 27.95 tonnes/ha) with 34.08 to 38.56 per cent increase in fruit yield over untreated control (17.17 tonnes/ha) closely followed by propargite 57% EC @1500 ml/ha (22.07 tonnes/ha).

Host plant resistance-cum-chemical control approach for the sustainable management of yellow mite, Polyphagotarsonemus latus (Banks)

host plant resistance-cum-chemical control approach for the sustainable management of yellow mite, <i>Polyphagotarsonemus latus</i> (Banks)

Effect of alternate food sources on biological parameters of Stethorus pauperculus Weise (Coleoptera: Coccinellidae)

The effect of different alternate food sources on survival, mating frequency, fecundity and egg hatchability of Stethorus pauperculus was tested under laboratory conditions. None of the alternative hosts was able to maintain fertility of the female S. pauperculus, except the primary hosts which included two spotted red spider mite (Tetranychus urticae Koch), sorghum mite (Oligonychus indicus (Hirst)) and yellow mite (Polyphagotarsonemus latus (Banks)). Although some eggs were laid when S. pauperculus was supplied with pollen and honey mixture, they did not hatch. The most effective food source for maintaining adult longevity was T. urticae (39.30±1.08 days), followed by sorghum mite, O. indicus (29.75±0.67 days) and yellow mite (25.25±0.78 days).

Efficacy of New Molecules and Botanicals against Chilli (Capsicum annuum L.) Pests

Field experiments were conducted during 2011-12, at Agricultural Research Station, UAS, Dharwad, Karnataka, South India to know the efficacy of new molecules and botanicals against chilli pests. viz., green peach aphid (Myzys persicae Sulzer, Aphis gossypi Glover), thrips (Scirtothrips dorsalis Hood), yellow mite (Polyphagotarsonemus latus Banks) and fruit borer (Helicoverpa armigera Hubner). The results revealed that thiamethoxam 25WG @ 1 g/l, abamectin 1.8EC @ 0.5ml/l, diafenthiuron 50 WP @ 0.75g/l were highly effective for the management of chilli sucking pests. Against H. armigera, novaluron 10 EC @ 0.75ml/l, emamectin benzoate 5SG @ 0.4g/l and spinosad45SC @ 0.3ml/l were found quite promising. The pesticides from biological origin and neem based formulations might be relatively less harmful to the natural enemies than insecticide like imidacloprid and cypermethrin. Significantly increased yield (4.65 q/ha) was recorded in diafenthiuron 50 WP @ 0.75g/l with higher net returns (Rs 22,661/ ha).

Sowing dates: a major factor on the infestation of insect pests and fibre yield of jute

The study was undertaken to assess the infestation of yellow mite and semilooper on jute in different dates of sowing. The results revealed that the early sown crop suffered more with yellow mite infestation and there was no significant effect of sowing times on semilooer infestation. There was no significant effect of insect pest pressure on fibre yield of the jute crop. Crop grown on mid-April was found to be more optimum with maximum of 30.30 q/ha fibre yield.

Studies on influence of genotypic diversity on yield, quality and incidence of white fly and yellow mite in Capsicum annuum L.

A field experiment was conducted with fifty one chilli (Capsicum annuum L.) genotypes to study the growth, yield, quality characters, white fly and yellow mite incidence during Rabi season of 2007-08 and 2008-09. The data on growth, yield performance, quality characters and pest incidence revealed significant variation among the different genotypes. Significantly the highest number of fruits per plant was recorded in genotype CA-29 (168.23) and it was lowest in genotype CA-2 (52.30) and it was statistically at par with genotypes CA - 15 (56.09) and CA-43 (56.20). Like number of fruits per plant, the significantly highest fresh yield was recorded in CA-29 (14.58 t/ha). Higher fruit yield was also recorded in genotype CA - 47 (13.35 t/ha) and CA-48 (13.18 t/ha). Ascorbic acid content in red ripe fruit varied from 75.89 to 167.21 mg/100 g fresh. The highest capsaicin content in the red ripe fruit was recorded in genotype CA -17 (1.13 %) followed by CA-4 (1.07%) and it was lowest in CA-7 (0.33%). Genotype CA - 45 was almost free from white fly incidence and lower incidence was also recorded in genotype CA-43 (0.40 /plant) followed by CA - 23 (0.50 / plant) and CA - 21 (8.10/ plant) was found most susceptible to white fly incidence. Among the different genotypes, CA - 22, CA - 24, CA - 25, CA - 27 and CA - 30 were free from mite infestation where as CA - 13 (13.60/leaf) was most susceptible to yellow mite incidence.

Field Applications of Silicon-Based Fertilizers Against Sugarcane Yellow Mite Oligonychus sacchari

Field trials were performed to examine the effects of foliar application of three silicon-based fertilizers (Potassium silicate, Agrisil, PQ Corporation, South Africa; Potassium silicate, NTS Australia and Silamol, Roam Chemie, Belgium) against sugarcane yellow mite Oligonychus sacchari on four sugarcane varieties: CP48-103, CP57-614, CP69-1062 and SP70-1143. Two applications of these fertilizers were applied before mite infestation, and the number of mites was recorded 10, 20, 30 and 40 days after second application of the silicon fertilizers. For evaluating the effects of silicon treatments on the predatory beetle, Stethorus sp.; the number of beetles was also recorded 10, 20, 30 and 40 days after second application of the silicon fertilizers. The results showed that there was a significant difference among silicon fertilizers and control group of mite and predatory beetle’s populations. The number of mites in the control group of all the varieties was between 9.17 and 14.02 after 40 days; whereas population density of mites reduced significantly in all the silicon treated plots in comparison with the control. In addition, population density of predatory beetles was affected by mite’s population and the number of beetles reduced in the treated plots. However, according to the importance of applying IPM programs in fields incorporating of acaricides with other reduce-risk strategies including biological control agents should be considered as a sugarcane IPM program.

Impact of yellow mite (Polyphagotarsonemus latus[Banks]) density on host's (Corchorus capsularis L.) phenology and assessment of yield loss under field conditions

Yellow mite, Polyphagotarsonemus latus [Banks] (Acari: Tarsonemidae) is one of the major pests of jute crops (Corchorus capsularis L.) in Bangladesh. In this study, indigenous varieties of jute were used for treatments, namely, CVL-1, CVE-3, BJC-7370 and BJC-83. The paired plot treatments (treated and untreated controls) were laid out under field conditions. The effects of yellow mite were studied at three stages of the jute plants: 60 days after sowing (DAS), 90 DAS and 120 DAS. A higher number of mite stages was observed up to 90 DAS and then declined up to 120 DAS in var. BJC-7370 among two other varieties, Deshi and Tossa. The percentage of infestation and damage indexes (scale 0–5) were measured to relate yellow mite injuries to the number of leaves, leaf area, fresh leaf weight, dry leaf weight, soluble solids, plant height, base diameter, fiber weight, stick weight, number of flowers per plant, number of pods, pod weight per plant, seeds per pod, seed weight and 1000 seeds' weight of plants infested at three different phenological stages. The highest fiber yield loss was found in the variety BJC-7370 (59.75%), followed by BJC-83 (55.56%), CVE-3 (54.30%) and CVL-1 (50.05). The highest stick yield losses were found in the following order: BJC-7370 (54.54%) > BJC-83 (51.17%) > CVL-1 (43.68%) > CVE-3 (37.80%) and BJC-7370 (30.33%) > CVL-1 (27.83%) > BJC-83 (24.16%) > CVE-3 (22.11%) for the highest seed yield under field conditions for Corchorus capsularis. High yellow mite population in untreated checks decreased plant growth and showed significant losses in yield production for the variety BJC-7370.

English

&nbsp; The yellow mite,&nbsp;Polyphagotarsonemus latus&nbsp;Banks (Acari: Tarsonemidae) is one of the most serious pests of jute crop (Corchorus olitorius&nbsp;L.) in Bangladesh. Jute plants of tossa (C. olitorius) varieties were considered as treatments including, O-9897,O-72,OM-1 and O-795. The paired plot treatments (miticide treated and miticide untreated control) were laid out under net house condition. The impact of yellow mite, were studied on three stages of jute plants: 60, 90 and 120 DAS. The higher number of mite stages observed up to 90 DAS then declined afterward up to 120 DAS in var. OM-1 among four C. olitorius varieties. A damage index scale (0-5) was to assess yellow mite injury to jute plants. The percent infestation and damage index was also used to relate yellow mite injury to different yield contributing characters of plants infested at three different phenological stages. The yield contributing characters of untreated plots showed significant damage at 60, 90 and 120 DAS in&nbsp;C. olitorius&nbsp;varieties compared to treatment plots. The highest fibre yield losses due to mite infestation was found in the variety OM-1 (74.71%) followed by O-795 (72.98%), O-72 (68.14%) and the lowest was in O-9897 (50.11%); the highest stick yield losses in OM-1(57.18%) followed by O-795 (49.43%), O-9897 (49.35%), the lowest was in O-72(48.92%)and the highest seed yield losses in O-795(64.34%)followed by O-72(48.21%),OM-1(44.55%), he lowest was in O-9897(42.69%) under net house condition. High yellow mite population in the untreated check decreased plant growth and showed significant fibre and stick weight loss in the variety OM-1 and seed weight loss in the variety O-795. &nbsp; Key words:&nbsp;Polyphagotarsonemus latus,&nbsp;Corchorus capsularis, abundance, yield.

Evaluation of pesticides against major pests of jute (Corchorus olitorius L.) in West Bengal, India

Among the pesticides evaluated against the jute pests under field conditions, endosulfan 35 EC at 350 g a.i./ha was found to be the most effective insecticide for controlling semilooper, Bihar hairy caterpillar and myllocerus weevil. Endosulfan and fenpropathrin provided good control of yellow mite as well. Even, endosulfan-treated plots gave maximum fibre and stick yield with greater benefit–cost ratio (BCR) over others. Next to endosulfan and chlorpyriphos, neemazal (azadirachtin 50,000 ppm) are useful and safer options against semilooper, Bihar having caterpillar, myllocerus and yellow mite. Methoxyfenocide 10 EC at 200g a.i./ha provided good control (70.60%) of S. obliqua even after 14 days of spraying, but it was not effective against other pests of jute. Further, almost similar efficacy of neemazal and chlorpyriphos was found against the pest complex of jute and based on BCR, neemazal could be an alternative choice over chlorpyriphos.

Incidence of pests in jute (Corchorus olitorius L.) ecosystem and pest–weather relationships in West Bengal, India

Experiment on jute crop was conducted during pre-kharif to kharif seasons (April to August) at Bidhan Chandra Krishi Viswavidyalaya (BCKV), West Bengal, India in a view to record the pest incidence on olitorius jute and to determine the weather parameters impacting on pest population in jute under West Bengal conditions. Seventeen different species of pests belonging to insects, mites and nematodes were found feeding on jute. Among them, jute semilooper (Anomis sabulifera Guen.), Bihar hairy caterpillar (Spilarctia obliqua Wlk.), grey weevil (Myllocerus discolor Bohemus), yellow mite (Polyphagotarsonemus latus Banks), stem weevil (Apion corchori Marshall), and root knot nematode, Meloidogyne incognita are causing economic damage to the crop and other pests were considered as minor pests. Correlation studies with weather parameters showed that incidence of semilooper was negatively correlated (r = −0.795 to −0.725) with the maximum temperature but had positive significant association with minimum temperature (r = 0.528–0.715), morning relative humidity (RH) (r = 0.579–0.857) and afternoon RH (r = 0.876). Bihar hairy caterpillar incidence also exhibited positive significant relationship with morning RH (r = 0.577) and afternoon RH (r = 0.545). Morning and afternoon RH and rainfall also had significant positive correlation with the incidence of M. discolor with r = 0.535, 0.570, and 0.700, respectively. None of the meteorological parameters had any significant influence on the incidence of A. corchori. Yellow mite incidence showed positive association with morning RH (r = 0.563–0.679) and afternoon RH (r = 0.526–0.618). Rainfall was found favourable for proliferation and incidence of M. discolor only but had a negative effect on the incidence of stem weevil and yellow mite. Thus climatic factors particularly temperature, relative humidity and rainfall played a pivotal role on occurrence and existence of different pests on jute crop.