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The developmental and reproductive biology of the two-spotted spider mite, Tetranychus urticae (Koch), a devastating polyphagous pest, were studied on five vegetables in summer (27-36 °C, RH 81-85 %) and winter (5-19 °C, RH 70-75 %) under prevailing laboratory conditions. Immature developmental time and adult longevity were inversely related to seasons. The results indicated that the development of the mite increased more rapidly on bean in summer than on the other tested hosts. The longest developmental period was 41.94 and 41.07 days for females and males, respectively, in winter when T. urticae was fed on cowpea. In contrast, it was the shortest (11.25 and 10.39 days) in summer while reared on bean. Lifetime fecundity (62.71) and daily fecundity (5.48) was the highest on bean in summer. The sex ratio (female:male) was the highest (0.76) on cowpea and the lowest (0.66) on brinjal in winter. Survivorship during immature development varied from 82.14 to 95.65 %, with the lowest rate in summer when reared on bean. Life table parameters were analysed and the generation time (T) was found the lowest (20.37) in summer when fed on bean, net reproductive rate (R0) was the highest (36.29) in summer on cowpea and both intrinsic rate of natural increase, rm (0.17), and finite rate of increase, λ (1.19), were the highest in summer when fed on bean. [ABSTRACT FROM AUTHOR]

Bangladesh Agricultural Research Institute (BARI) released two beautiful Lilium varieties in 2020. In the same year the farmers in Gazipur district reported a set of disease symptoms on these flowers and alerted the Plant Pathology Division of BARI. Subsequent investigation confirmed the symptoms as Botrytis gray mold (BGM), caused by Botrytis cinerea . The pathogen identity was confirmed through ITS gene sequencing. A series of in vitro and in planta experiments conducted to understand the symptoms, the optimal growth condition for the pathogen, potential resistant Lilium genotypes, effective chemical treatments and potential of biological control agents to combat the disease. B. cinerea exhibited the highest growth in V8 media (88.55 mm) at pH6 (85.32 mm) and temperature between 20 and 25 °C (89.56 mm), and pH6 (85.32 mm). Screening revealed that five oriental-originated genotypes provided lower disease incidence (31.66-41.66 %), and were categorized as moderately resistant to resistant in disease reaction. Six fungicides successfully reduced mycelial growth in vitro . Moreover, Ipridione provided the lowest % disease incidence (27.11) and % disease severity (5.33) in the in planta nethouse experiment. Therefore, this fungicide was recommended to the farmers initially. Additionally, two fungal biocontrol agents Epicoccum nigrum EJS002 and Trichoderma ThC003, demonstrated effectiveness in reducing leaf lesion size over control in a detach leaf assessment technique. In conclusion, this study presents BGM of Lilium as a farmers issue for the first time in Bangladesh. It also provides valuable insights into its management, recommending specific chemical fungicides for farmers to use, and two fungal antagonists ( E. nigrum EJS002 and Trichoderma ThC003) as potential disease control agent., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Cinnamomum tamala (bay leaf) is widely used for culinary and medicinal purposes in South Asia. A leaf blight/spot disease was first discovered on nearly 90% of C. tamala plants with a mean severity of 48% to 74.4% in Gazipur and Bogura, Bangladesh, in 2019. The present study identified and characterized the causal organism and formulated the optimum growth conditions and effective fungicides for the chemical control of the pathogen. The characteristic symptoms on the infected leaves appeared circular to oval reddish-brown spots with raised margins and often developed in tear-stain patterns. Severe infection of C. tamala sapling resulted in dieback symptoms with leaf defoliation. A fungus with floccose, dense, white colonies with well-differentiated acervuli was isolated from the infected leaves. Combined cultural, morphological, and molecular characteristics identified the pathogen as Colletotrichum siamense. Inculcating healthy leaves and 1-year-old saplings of C. tamala with a conidial suspension of the fungus reproduced the same symptoms observed in the bay leaf orchard. The highest mycelial growth was recorded on V-8 Juice Agar media, while the maximum radial mycelial growth and level of sporulation of the fungus were significantly higher in incubation temperature 30°C. Fungicide trials showed that carbendazim 50 WP, azoxystrobin, mancozeb, and trifloxystrobin, either singly or in combination, successfully reduced fungal mycelial growth in vitro. Therefore, disease management strategies should be opted to halt the further spread of this issue. To our knowledge, this is the first study to document the incidence of Colletotrichum leaf blight on C. tamala in Bangladesh and even in the world., (© 2023 Wiley-VCH GmbH.)