scholarly journals Incidence of Major Insect Pests and Natural Enemies in Three Rice Growing Seasons of Bangladesh

2020 ◽  
Vol 23 (1) ◽  
pp. 35-43
Author(s):  
S Afrin ◽  
M N Bari ◽  
M M M Kabir ◽  
A B M A Uddin ◽  
S S Haque

Incidence of insect pests and their associated natural enemies was investigated from July 2017- June 2018 at six locations (Gazipur, Rajshahi, Barishal, Sonagazi, Rangpur, Cumilla) of Bangladesh to identify their major occurrence period as well as their incidence in three rice growing seasons, (Aus, T. Aman, and Boro). Among the tested locations, marked differences were found in the composition of insect pest and natural enemies. Higher number of pest population was found at Gazipur with 80,000 individuals for insect pest and 40,000 individuals for natural enemies. At least one peak for major insect pest and natural enemies suggested their specific occurrence period across the locations. Among the insect pests, major peak of GLH was found at Gazipur and Rajshahi during T. Aman season with 4,000 individuals for each location. In contrast, BPH population was as high as 10,000 individuals for Gazipur in October during T. Aman season. Additionally, it was high at Rajshahi in October and November with around 2,000 individuals of BPH. For WBPH, one major peak was found in October at Gazipur and Rajshahi with 10,000 and 2,000 individuals respectively. For YSB, it was higher at Rajshahi in October with over 6,000 individuals during T. Aman season. Moreover, one major peak also observed in Barishal with over 2,000 individuals in November. Among natural enemies, CDB population was observed mainly at three locations in between October and November with 900 individuals for Gazipur, 400 individuals for Rajshahi and 200 individuals for Barishal during T. Aman season. In contrast, for STPD population, two major peaks were found in Barishal with 6,000 and 5,000 individuals in December and March respectively during Boro season. For GMB population, it was observed at Gazipur in November with more than 20,000 individuals during T. Aman season whereas Rajshahi had around 2,000 individuals in the same month. However, higher incidence of GLH, BPH, and WBPH at Gazipur and Rajshahi suggested availability of insect pests during T. Aman season. In contrast, higher YSB incidence at Barishal and Rajshahi indicated their abundance in those areas. On the other hand, incidence of natural enemies at Gazipur indicated presence of greater biological control compared with other locations. In future, this information could serve as a reliable source in strengthening rice pest monitoring services as well as effective pest control in Bangladesh. Bangladesh Rice j. 2019, 23(1): 35-43

1977 ◽  
Vol 28 (2) ◽  
pp. 319 ◽  
Author(s):  
GO Furness

Chemical control of the mealybug Pseudococcus longispinus (Targioni-Tozzetti) was most effective if sprays were applied when the mealybugs were in the dispersive crawler stage and when the host plant afforded the least shelter. A two-spray program with sprays applied in August and late November effectively controlled a dense infestation of the mealybug on citrus. Red scale (Aonidiella aurantii (Maskell)), the major insect pest of citrus, was also effectively controlled. An overall pest management program has been developed for citrus in which all insect pests are controlled by combination of natural enemies and insecticides as required. Outbreaks of the mealybug, and other secondary pests, are controlled by sprays of aminocarb or methomyl. These two insecticides prevented the population resurgence of mealybugs in the subsequent generation which occurred when maldison was used. Bioassays showed that aminocarb and methomyl were toxic for less than a week to the mealybug and to parasites and predators, whereas maldison and methidathion were toxic to the parasites and predators for about a month. Parasite pupae inside the host mealybug survived sprays of maldison and aminocarb. It is suggested that natural enemies emerging after spraying, from resistant or protected stages, survive sprays of aminocarb and methomyl but not sprays of more persistent insecticides like maldison; and that these survivors continue to suppress populations of their hosts. Hence aminocarb and methomyl are probably specific in their action against the mealybug and the other secondary pests of citrus because of their short persistence.An insecticide check experiment failed to demonstrate that natural enemies significantly reduce populations of the mealybug. Possible reasons for the failure are discussed.


Author(s):  
S. Pal ◽  
S. Samanta ◽  
A. Banerjee

Background: Field pea, Pisum sativum L. is an important winter-season pulse crop. It is subjected to damage by both field and storage insect pests and approximately 10-15 per cent reduction in yield was reported due to the infestation of different insect pests. Among these, pulse aphid (Aphis craccivora Koch.) affects plant physiology directly by removal of nutrients or indirectly by dispersal of various viral diseases. The present investigation has been aimed to study the seasonal fluctuations of aphids and their natural enemies as well as their correlation. Another objective was to know the effect of various weather parameters on pulse aphids and their natural enemies which ultimately would be helpful to develop a forewarning model.Methods: The field experiment was conducted at the A-B Block Farm of Bidhan Chandra Krishi Viswavidyalaya, Nadia, West Bengal using two varieties of field pea (KPMR 935 and IFPD 122) during rabi seasons of two consecutive years of 2017-18 and 2018-19 following a Randomized Block Design with three replications. After recording the total population of both pests (nymphs and adults) and their natural enemies across the season, the mean population was worked out and used for correlation and regression studies along with the weather parameters. Result: Maximum aphid population was noticed during the peak pod formation stage of the crop irrespective of the varieties. The pest population was very strongly correlated with the incidence of coccinellid and ant population in both test varieties. Among the weather parameters, both maximum and minimum temperature and sunshine hour showed a positive correlation with the pest population and their natural enemies but relative humidity and rainfall showed a negative correlation. Regression studies indicated that temperature and relative humidity were the most influencing factors over the incidence of aphid in both the seasons.


Insects ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 128 ◽  
Author(s):  
Shovon Chandra Sarkar ◽  
Endong Wang ◽  
Shengyong Wu ◽  
Zhongren Lei

Companion planting is a well-known strategy to manage insect pests and support a natural enemy population through vegetative diversification. Trap cropping is one such type of special companion planting strategy that is traditionally used for insect pest management through vegetative diversification used to attract insect pests away from the main crops during a critical time period by providing them an alternative preferred choice. Trap crops not only attract the insects for feeding and oviposition, but also act as a sink for any pathogen that may be a vector. Considerable research has been conducted on different trap crops as companion plant species to develop improved pest management strategies. Despite this, little consensus exists regarding optimal trap cropping systems for diverse pest management situations. An advantage of trap cropping over an artificially released natural enemy-based biological control could be an attractive remedy for natural enemies in cropping systems. Besides, many trap crop species can conserve natural enemies. This secondary effect of attracting natural enemies may be an advantage compared to the conventional means of pest control. However, this additional consideration requires a more knowledge-intensive background to designing an effective trap cropping system. We have provided information based on different trap crops as companion plant, their functions and an updated list of trap cropping applications to attract insect pests and natural enemies that should be proven as helpful in future trap cropping endeavors.


Author(s):  
Michele Preti ◽  
François Verheggen ◽  
Sergio Angeli

AbstractIntegrated pest management relies on insect pest monitoring to support the decision of counteracting a given level of infestation and to select the adequate control method. The classic monitoring approach of insect pests is based on placing in single infested areas a series of traps that are checked by human operators on a temporal basis. This strategy requires high labor cost and provides poor spatial and temporal resolution achievable by single operators. The adoption of image sensors to monitor insect pests can result in several practical advantages. The purpose of this review is to summarize the progress made on automatic traps with a particular focus on camera-equipped traps. The use of software and image recognition algorithms can support automatic trap usage to identify and/or count insect species from pictures. Considering the high image resolution achievable and the opportunity to exploit data transfer systems through wireless technology, it is possible to have remote control of insect captures, limiting field visits. The availability of real-time and on-line pest monitoring systems from a distant location opens the opportunity for measuring insect population dynamics constantly and simultaneously in a large number of traps with a limited human labor requirement. The actual limitations are the high cost, the low power autonomy and the low picture quality of some prototypes together with the need for further improvements in fully automated pest detection. Limits and benefits resulting from several case studies are examined with a perspective for the future development of technology-driven insect pest monitoring and management.


Agriculture ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 644
Author(s):  
Luis Cruces ◽  
Eduardo de la Peña ◽  
Patrick De Clercq

Over the last decade, the sown area of quinoa (Chenopodium quinoa Willd.) has been increasingly expanding in Peru, and new production fields have emerged, stretching from the Andes to coastal areas. The fields at low altitudes have the potential to produce higher yields than those in the highlands. This study investigated the occurrence of insect pests and the natural enemies of quinoa in a traditional production zone, San Lorenzo (in the Andes), and in two new zones at lower altitudes, La Molina (on the coast) and Majes (in the “Maritime Yunga” ecoregion), by plant sampling and pitfall trapping. Our data indicated that the pest pressure in quinoa was higher at lower elevations than in the highlands. The major insect pest infesting quinoa at high densities in San Lorenzo was Eurysacca melanocampta; in La Molina, the major pests were E. melanocampta, Macrosiphum euphorbiae and Liriomyza huidobrensis; and in Majes, Frankliniella occidentalis was the most abundant pest. The natural enemy complex played an important role in controlling M. euphorbiae and L. huidobrensis by preventing pest resurgence. The findings of this study may assist quinoa producers (from the Andes and from regions at lower altitudes) in establishing better farming practices in the framework of integrated pest management.


2015 ◽  
Vol 43 (1) ◽  
pp. 23
Author(s):  
Siti Herlinda ◽  
Amarilisa Kusuma ◽  
Suwandi . ◽  
Andi Wijaya

The advantages of ratooning rice are to save water, cost production, labor, preparation time for planting and harvesting, but the ratooning productivity is still low.  This research aimed to study the effect of the bioinsecticide and compost extract on ratooning rice production and insect populations. The ratooning rice was applied by bioinsecticide, compost extract, and combination of bioinsecticide and compost extract with dose 2 L ha-1  per application, respectively. Data of agronomic variables were statistically analyzed using analysis of variance, whereas insect pest population data were analyzed using Chi Square test. The seedling height of ratoon applied by compost extract was the highest among treatments. The number of productive tillers per clumps and rice production on plot applied by compost extract were higher than the insecticide treatment. At the age of 17 day-ratooning rice, application bioinsecticide reduced the population of insect pests, such as Ciccadulina bipunctata, Recilia dorsalis, Nilaparvata lugens, and Nephotettix nigropictus. Thus, application of compost extract tended to improved the growth and production of the ratooning rice, while the bioinsecticide decreased the insect pest population.<br />Keywords: Beauveria bassiana, rice growth, production


2021 ◽  
Vol 12 (3) ◽  
pp. 285-295
Author(s):  
Augustine Mansaray ◽  
Abdul Babatunde Karim ◽  
Thomas B R Yormah ◽  
Abdul Rahman Conteh ◽  
Marie Yomeni

Field trials were conducted in 2015/2016 and 2016/2017 cropping seasons in three agro-climatic zones of the country to evaluate the productivity and insect pests population dynamics of cassava as a response to spatial arrangement, plant architecture and cropping systems. The treatments consisted of seven cropping associations, two cassava architectures and two spatial arrangements. The study reveals that yield parameters of cassava were higher in cassava-soybean system at all locations. The number of marketable roots and forage yield were on average higher when the erect cassava variety was intercropped with the legumes using the 1 m x 1m spatial arrangement. On the other hand, root yield and canopy width were higher when the 2 m x 0.5 m spatial arrangement and the branched cassava architecture was used respectively. In general, yield parameters were higher at Segbwema expect for forage yield that was higher at Makeni. With respect to cassava insect pests, higher percentage incidences and severity scores were recorded on sole cassava and when the branched cassava variety was intercropped with legumes using the 2 m x 0.5 m spatial arrangement of cassava. In addition, cassava insect pests incidences were only observed at 6 MAP and 9MAP and were higher in Segbwema compared to the other locations. Thus, in order to improve productivity of cassava with low insect pest infestation, the erect cassava variety should be intercropped with soybean at a spatial arrangement of 1 m x 1 m.


1927 ◽  
Vol 18 (1) ◽  
pp. 13-16 ◽  
Author(s):  
W. R. Thompson

The importation of parasites from the native home of introduced insect pests now constitutes a recognised part of entomological practice in most countries under civilised control. However, since the method is still in the experimental stage, and since long periods of time often elapse before the parasites colonised become sufficiently abundant to exert any appreciable influence on the host, the entomologist often finds it necessary, in order to avert disaster, to utilise remedies which, though temporary, are more immediately effective. To this end he employs some one or other of the various methods of mechanical control, by which the population of the insect pest can be at once greatly reduced.But in many cases, these methods of attack affect the parasites as well as the hosts. It is therefore important to consider what influence they will have upon the progress of the natural enemies and whether, in order to obtain the temporary relief afforded by mechanical methods, we are not sacrificing the hope of permanent control.We have at present no data permitting us to attack this problem from the experimental angle ; but it can be studied in a broad general way when reduced to mathematical terms.


1991 ◽  
Vol 67 (5) ◽  
pp. 500-505 ◽  
Author(s):  
V. G. Nealis

Forest insect pest management differs from pest management in other renewable-resource industries because of the relative complexity and stability of the forest environment. An important component of this complexity is the rich fauna of natural enemies attacking most forest insect pests. Understanding the relationship between forest insect pests and their natural enemies would permit better insight into the dynamics of pest populations.The active release of natural enemies in inoculative or inundative release strategies is a direct application of biological control to pest management. The conservation of resident natural enemies is an indirect biological control method with great potential. Knowledge of the ecology of natural enemies can be used to modify other forest practices such as reforestation and insecticide use to conserve or enhance the action of natural enemies.


2008 ◽  
Vol 48 (12) ◽  
pp. 1531 ◽  
Author(s):  
Joanne C. Holloway ◽  
Michael J. Furlong ◽  
Philip I. Bowden

Beneficial invertebrates (predators and parasitoids) can make significant contributions to the suppression of insect pest populations in many cropping systems. In Australia, natural enemies are incorporated into integrated pest management programs in cotton and horticultural agroecosystems. They are also often key components of effective programs for the management of insect pests of grain crops in other parts of the world. However, few studies have examined the contribution of endemic natural enemies to insect pest suppression in the diverse grain agroecosystems of Australia. The potential of these organisms is assessed by reviewing the role that natural enemies play in the suppression of the major pests of Australian grain crops when they occur in overseas grain systems or other local agroecosystems. The principal methods by which the efficacy of biological control agents may be enhanced are examined and possible methods to determine the impact of natural enemies on key insect pest species are described. The financial and environmental benefits of practices that encourage the establishment and improve the efficacy of natural enemies are considered and the constraints to adoption of these practices by the Australian grains industry are discussed.


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