Search

Canola (Brassica napus L.) is one of the economically important crops of Pakistan and mustard aphid, Lipaphis erysimi Kalt. (Hemiptera: Aphididae), is a serious threat to this crop. This experiment was conducted with an aim to screen out selected canola cultivars for their tolerance against L. erysimi infestation under glasshouse conditions. Experiment was carried out using completely randomized design with ten replications for each treatment during growing seasons of 2018 and 2019. Data were documented based on the tolerance indices (TI) and proportional plant dry weight change (DWT) to identify tolerance of canola crop. Results revealed that commercial cultivar 'Zahoor' comparatively performed well despite higher number of aphids found on itas compared its other counterparts "Abaseen, Omega and KS-75" and hence, was identified as tolerant to mustard aphid. This cultivar also exhibited strong vigor against mustard aphid and minimal symptoms of damages were observed. The yield losses based on DWT and TI in susceptible cultivar "Abaseen" was 40.79%, whereas it was 23.56% in Zahoor which confirmed the reduced percent yield losses in the later genotype. This study identified "Zahoor" as the most tolerant cultivar to mustard aphid followed by KS-75 and Omega hence, other susceptible cultivars should be replaced by Zahoor to attain higher and sustainable yield production in canola. [ABSTRACT FROM AUTHOR]

Potato (Solanum tuberosum L.) is an important vegetable food crop in Pakistan. Myzus persicae is an insect pest of potato, feeding on phloem tissues of leaves of potato plant and significantly reduces the yield of potato. Antixenosis experiments were performed to assess the resistance potential of eight different potato cultivars against M. persicae under glasshouse conditions for three different durations of time (12, 24 and 48 hours) during spring and autumn potato growing seasons of 2016. Both the experiments were conducted using a completely randomized design. Each experiment having eight treatments and each treatment was replicated 10 times. The replicated pots containing each of the eight potato cultivars were infested with 100 and 200 adult of M. persicae. Significant antixenosis effects among the tested potato cultivars were observed while the different durations of M. persicae infestation on potato cultivars also displayed significant antixenosis effects against M. persicae during the spring and autumn experiments in 2016. During both experiments, Sarpo Mira displayed the lowest number of adults per plant on release of 100 and 200 adults per plant. Sarpo Mira showed M. persicae infestation of 3.3 and 2.4 per plant per pot on release of 100 adults per plant during spring and autumn seasons, respectively while an infestation of 5.3 per plant 4.7 per plant on Sarpo Mira was observed on release of 200 adults of M. persicae during spring and autumn seasons, respectively. FD-70 had the highest number of M. persicae (13.7 per plant) in the pots released with 100 M. persicae during spring season while Asterix showed the highest number of M. persicae (13.8 per plant) in pots infested with 200 M. persicae during autumn season. Sarpo Mira also appeared to be the most resistant potato cultivar against M. persicae at 12, 24 and 48 hours post infestation of M. persicae. Overall, this study revealed the resistant potential of potato cultivar Sarpo Mira against M. persicae. [ABSTRACT FROM AUTHOR]

Pyrilla perpusilla (Walker) is one of the devastating pests which decrease yield directly and indirectly of sugarcane crop. For the safe management of P. perpusilla, field experiments were conducted to find the population of Pyrilla perpusilla on 12 different sugarcane varieties under field conditions at two different districts Charsadda and district Dera Ismail Khan of Khyber Pakhtunkhwa. Plot size 36×16 m (length × width) was selected in both localities for the cultivation of sugarcane varieties (CP77/400, Jhang 59, 2086, US-633, YT-55, CPF-252, CPF-246, CPF-251, CPF-247, CPF-250, CPF-248, and CPF-249) in Feb 2020. Each variety was planted in sub-plot size 3×2 meters having 3 rows and 5plants/row in randomized complete block design (RCBD) with three replications. The data was recorded from Mar-Nov from fresh and ratoon crops of the year 2020 and 2021, respectively. The leaves (top, middle, and bottom) of five plants in each subplot was observed randomly for data collection every fortnight in all replications. The total mean population of Pyrilla perpusilla (eggs cluster and nymphs/adults) was recorded from the leaves of the plants. The experimental results were of the view that could be used to conclude the research that the different varieties have different behaviour towards hosting the P. perpusilla. The population Pyrilla perpusilla (eggs clusters and nymphs/adults) were found highest on CPF-252 while least population of P. perpusilla was recorded on CPF-249 in both location and both years of the study (2020-2021) with its peak activity in the month of August. Significantly, positive correlation was recorded between P. perpusilla (eggs clusters and nymphs/adults) population infestation and average abiotic factors (temperature, humidity and rainfall). The correlation between leaf length and leaf width with P. perpusilla (eggs clusters and nymphs/adults) was significantly positive, the correlation of P. perpusilla (eggs clusters and nymphs/adults) with cane length was non-significant but positive while negative non-significant correlation was found between P. perpusilla (eggs clusters and nymphs/adults) population and cane diameter. The population of P. perpusilla on sugarcane variety CPF-249 was comparatively less which can be combine in future IPM programmes for the suppression of P. perpusilla infestation. [ABSTRACT FROM AUTHOR]

Peach flat-headed borer, Sphenoptera dadkhani (Oben.) is the major insect-pest of stone fruit orchards. Survey of three districts of Khyber Pakhtunkhwa revealed the highest mean infestation in plum orchards of district Peshawar (89.60%), followed by Nowshera (75.79%) and Swat (45.42%). In peach orchards, highest mean infestation was recorded in Peshawar (88.33%), followed by Nowshera (72.77%) and Swat (53.72%). The mean infestation of 70.86% was recorded in apricot orchards in Peshawar, followed by Nowshera (62.40%) and Swat (40.73%). Bordeaux mixture treatment applied to tree trunks was very effective in reducing the borer infestation during dormant season. After pruning orchards, Nurelle-D 505EC and Triazofos 40EC @ 75ml of each proved to be the best toxicants, which showed synergistic effect in Bordeaux mixture (Copper oxychloride 75g + Lime 3kg + water 10L) in reducing borer infestation (exit holes/ gum points) in the month of January. [ABSTRACT FROM AUTHOR]