scholarly journals Studies on insect diversity in jasmine (Jasminum sambac L.) ecosystem

2021 ◽  
Vol 42 (6) ◽  
pp. 1470-1477
Author(s):  
U. Pirithiraj ◽  
◽  
R.P. Soundararajan ◽  
C.G.L. Justin ◽  
V. Lakshmanan ◽  
...  

Aim: Study was carried out to record the abundance and diversity of insects in jasmine (Jasminum sambac L.) ecosystem. Methodology: To determine insect pests, natural enemies and non-insect diversity, fortnight observations were taken from second fortnight of September'19 to March'20 on insect population at three adjacent locations. Abundance and diversity indices were computed using mean data. The management practices, presence of weeds and adjacent cropping systems were also recorded at three locations to determine the reasons for variation in the diversity of organisms. Results: A total of 3335 individuals arthropods belonging to 55 species, which included 32 species of herbivores and 23 species of natural enemies were recorded throughout the study period. Location 3 had perennial crops in the vicinity, un-weeded ecosystem with no chemical inputs. Among various diversity indices calculated, Margalef Richness Index of herbivores was higher at location 3 (1.67) than location 1 (1.17) and 2 (0.76). Interpretation: The abundance and diversity of insects in different jasmine ecosystem depends on the chemical inputs and adjacent cropping system.

2016 ◽  
Vol 41 (3) ◽  
pp. 461-470
Author(s):  
MA Bakar ◽  
MMH Khan

In order to measure the diversity of insect pests and natural enemies in rice ecosystem, the present study was conducted in the research farm of Patuakhali Science and Technology University, Dumki, Patuakhali during the period from January to June, 2012 in boro rice season. Diversity indices of insect pests and their natural enemies were found to be affected by the combined effect of rice growth stages and management practices. Diversity indices of insect pests and their natural enemies differed according to treatments and crop growth stages. In case of insect pests, the untreated control treatment showed the highest diversity index (1.67) at maximum tillering stage and spray (Bipolar 55EC @ 10 ml/10 L of water) + perching at early tillering stage also showed highest richness (26.14) and the highest evenness (0.921) in spray at seedling stage. The highest reciprocal form of Berger-Parker's Dominance index (D) was found in untreated control at maximum tillering stage (3.03) for insect pests. In case of natural enemies, perching showed the highest diversity index (1.88) at reproductive stage. Spraying of insecticide at early tillering stage also showed highest richness (5.06) and the highest evenness (0.982) was in perching at seedling stage. The highest D value was found in perching at reproductive stage (4.67) for natural enemies.Bangladesh J. Agril. Res. 41(3): 461-470, September 2016


2020 ◽  
Vol 49 (3) ◽  
pp. 572-579
Author(s):  
Alexandre M M C Loureiro ◽  
Vilis O Nams ◽  
Scott N White ◽  
G Christopher Cutler

Abstract Carabidae (Coleoptera) are important natural enemies of many insect pests in various cropping systems. Their population dynamics and how they disperse determine how effective they are at carrying out the natural enemy function. There are robust patterns of community dynamics in annual cropping systems, but it is unclear if these would carry over into a relatively underexplored North American perennial crop. In Nova Scotia lowbush blueberry fields, we found that Carabidae diversity did not change with distance from field edge nor with time. Their activity density also did not change with time, but it did change with distance from field edge. We also found that the most abundant carabid of lowbush blueberry, Harpalus rufipes (De Geer) (Coleoptera: Carabidae), can disperse approximately 14.5 m/d. Our results shed more light on the community dynamics of Carabidae in lowbush blueberry fields and can help growers make informed decisions when it comes to incorporating natural enemies into their pest management practices.


1993 ◽  
Vol 28 (3-5) ◽  
pp. 691-700 ◽  
Author(s):  
J. P. Craig ◽  
R. R. Weil

In December, 1987, the states in the Chesapeake Bay region, along with the federal government, signed an agreement which called for a 40% reduction in nitrogen and phosphorus loadings to the Bay by the year 2000. To accomplish this goal, major reductions in nutrient loadings associated with agricultural management practices were deemed necessary. The objective of this study was to determine if reducing fertilizer inputs to the NT system would result in a reduction in nitrogen contamination of groundwater. In this study, groundwater, soil, and percolate samples were collected from two cropping systems. The first system was a conventional no-till (NT) grain production system with a two-year rotation of corn/winter wheat/double crop soybean. The second system, denoted low-input sustainable agriculture (LISA), produced the same crops using a winter legume and relay-cropped soybeans into standing wheat to reduce nitrogen and herbicide inputs. Nitrate-nitrogen concentrations in groundwater were significantly lower under the LISA system. Over 80% of the NT groundwater samples had NO3-N concentrations greater than 10 mgl-1, compared to only 4% for the LISA cropping system. Significantly lower soil mineral N to a depth of 180 cm was also observed. The NT soil had nearly twice as much mineral N present in the 90-180 cm portion than the LISA cropping system.


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.


1989 ◽  
Vol 79 (1) ◽  
pp. 115-121 ◽  
Author(s):  
Clifford S. Gold ◽  
Miguel A. Altieri ◽  
Anthony C. Bellotti

AbstractCassava intercropped with cowpea in Colombia had lower numbers of Aleurotrachelus socialis Bondar and Trialeurodes variabilis (Quaintance) per leaf and per plant than did monoculture cassava. These differences persisted for up to six months after harvest of the cowpea. These results are examined in light of the natural enemies hypothesis, which suggests that natural enemies may be favoured in diversified systems, thereby reducting herbivore load. In this regard, the effects of different cropping systems on the whitefly predator Delphastus pusillus (Le Conte) and on the combined action of the parasitoids Amitus aleurodinus Haldeman and Eretmocerus aleyrodiphaga (Risbec) are discussed. D. pusillus displayed a functional responce and was more abundant in monocultures than in intercrops. Predator:prey ratios were similar between treatments and so low that predation appeared to have little impact on whitefly numbers. Parasitism levels of Aleurotrachelus socialis were not affected by crop combinations. The data suggest that the activity of the natural enemies does not explain cropping system effects on cassava whitefly populations.


Agronomy ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 841 ◽  
Author(s):  
Costanza Ceccanti ◽  
Marco Landi ◽  
Daniele Antichi ◽  
Lucia Guidi ◽  
Luigi Manfrini ◽  
...  

The sustainability of current farming systems has been questioned in the last decades, especially in terms of the environmental impact and mitigation of global warming. Also, the organic sector, which is supposed to impact less on the environment than other more intensive systems, is looking for innovative solutions to improve its environmental sustainability. Promisingly, the integration of organic management practices with conservation agriculture techniques may help to increase environmental sustainability of food production. However, little is known about the possible impact of conservation agriculture on the content of bioactive compounds in cash crops. For this reason, a two-year rotation experiment used 7 cash crops (4 leafy vegetables and 3 fruit crops) to compare integrated (INT), organic farming (ORG), and organic no-tillage (ORG+) systems to evaluate the possible influence of cropping systems on the nutritional/nutraceutical values of the obtained fruits and leafy vegetables. The results pointed out specific responses based on the species as well as the year of cultivation. However, cultivation with the ORG+ cropping system resulted in effective obtainment of fruits and vegetables with higher levels of bioactive compounds in several cases (11 out 16 observations). The ORG+ cropping system results are particularly promising for leafy vegetable cultivation, especially when ORG+ is carried out on a multi-year basis. Aware that the obtained data should be consolidated with longer-term experiments, we conclude that this dataset may represent a good starting point to support conservation agriculture systems as a possible sustainable strategy to obtain products with higher levels of bioactive compounds.


Soil Research ◽  
1999 ◽  
Vol 37 (2) ◽  
pp. 279 ◽  
Author(s):  
M. J. Bell ◽  
P. W. Moody ◽  
S. A. Yo ◽  
R. D. Connolly

Chemical and physical degradation of Red Ferrosols in eastern Australia is a major issue necessitating the development of more sustainable cropping systems. This paper derives critical concentrations of the active (permanganate-oxidisable) fraction of soil organic matter (C1) which maximise soil water recharge and minimise the likelihood of surface runoff in these soils. Ferrosol soils were collected from commercial properties in both north and south Queensland, while additional data were made available from a similar collection of Tasmanian Ferrosols. Sites represented a range of management histories, from grazed and ungrazed grass pastures to continuously cropped soil under various tillage systems. The concentration of both total carbon (C) and C1 varied among regions and farming systems. C1 was the primary factor controlling aggregate breakdown, measured by the percentage of aggregates <0·125 mm (P125) in the surface crust after simulated rainfall. The rates of change in P125 per unit change in C1 were not significantly different (P < 0·05) for soils from the different localities. However, soils from the coastal Burnett (south-east Queensland) always produced lower P125 (i.e. less aggregate breakdown) than did soils from the inland Burnett and north Queensland locations given the same concentration of C1. This difference was not associated with a particular land use. The ‘critical’ concentrations of C1 for each region were taken as the C1 concentrations that would allow an infiltration rate greater than or equal to the intensity of a 1 in 1 or 1 in 10 year frequency rainfall event of 30 min duration. This analysis also provided an indication of the risk associated with the concentrations of C1 currently characterising each farming system in each rainfall environment. None of the conventionally tilled Queensland Ferrosols contained sufficient C1 to cope with rainfall events expected to occur with a 1 in 10 frequency, while in many situations the C1 concentration was sufficiently low that runoff events would be expected on an annual basis. Our data suggest that management practices designed both to maximise C inputs and to maintain a high proportion of active C should be seen as essential steps towards developing a more sustainable cropping system.


2017 ◽  
Vol 9 (9) ◽  
pp. 210 ◽  
Author(s):  
M. A. Quddus ◽  
M. J. Abedin Mian ◽  
H. M. Naser ◽  
M. A. Hossain ◽  
S. Sultana

The experiment was conducted to measure crop yields, nutrient concentration, nutrient uptake and balance by using different nutrient management practices for mustard-mungbean-T. aman rice cropping system in calcareous soil of Madaripur, Bangladesh. Different nutrient management practices were absolute nutrient control (T1); farmer’s practice (T2); AEZ based nutrient application (T3) and soil test based nutrient application (T4). The practices were compared in a randomized completely block design with three replications over two consecutive years. The average yield through application of soil test based nutrient (T4) was showed effective to get highest yields of mustard (1530 kg ha-1), mungbean (1632 kg ha-1) and T. aman rice (4729 kg ha-1). The same practices (T4) exhibited the greatest nutrients uptake by the test crops. The apparent balance of N and K was negative; however it was less negative and less deficiency detect in T4 treatment. Positive balance of P observed in all practices except in T1. There was a positive S balance (7.60 kg ha-1) in T4 but negative in T1, T2 and T3. Zinc balance was found positive in T3 and T4 and negative in T1 and T2. Boron balance in the system was neutral or slightly positive in T1 and negative in T2 but positive in T3 and T4. Organic matter, N, P, S, Zn and B status in soil was improved by T4 treatment. The results suggested that the soil test based nutrient application is viable and sustainable for mustard-mungbean-T. aman rice cropping system in calcareous soils of Bangladesh.


Author(s):  
P. Parthiban ◽  
C. Chinniah ◽  
R. K. Murali Baskaran ◽  
K. Suresh ◽  
A. Ravi Kumar

Field experiment was carried out during 2014 – 2015 at DARS, Chettinad, Sivagangai district of Tamil Nadu to find out cost-effective groundnut based inter-cropping system for the management of key insect pests. Groundnut (Arachis hypogaea Linnaeus; Variety: VRI II) when intercropped with bajra (Pennisetum glaucum L.; Variety: Co 7), maize (Zea mays L.; Variety; Co 6) and sorghum (Sorghum bicolor L.; Variety: Co 30) 4:1 ratio harboured significantly less mean population of sucking pests viz. leafhopper, Empoasca kerri Pruthi, Aphids, Aphis craccivora Koch and Thrips, Scirtothrips dorsalis Hood recording 23.05, 24.81 and 25.47 nos./10 plants, 21.27, 23.52 and 22.44 nos./2.5 cm shoot and 11.15, 12.62 and 12.19 nos./5 leaflet respectively, whereas intercropping with redgram (Cajanus cajan L.; Variety: VBN (Rg) 3), marigold (Tagetes erecta L.; Variety: MDU 1), sesame (Sesamum indicum L.; Variety: Co 1) and onion (Allium cepa L.; Variety: Co 1) recorded high mean population as compared to other cropping systems while groundnut as pure crop recorded the highest mean population of 33.14 nos./10 plants, 33.22 nos./2.5 cm shoot and 19.00 nos./5 leaflet respectively.


2021 ◽  
Vol 42 (4) ◽  
pp. 1053-1061
Author(s):  
M. Kumar ◽  
◽  
S. Mitra ◽  
A. Bera ◽  
M.R. Naik ◽  
...  

Aim: Assessment of energy input output relationship, greenhouse gases emission and carbon footprint of diversified jute-rice cropping systems under different nutrients and crop residue management practices. Methodology: The inventory was prepared for all inputs required for crop cultivation and outputs of crops in cropping systems. These inputs and outputs were converted into energy by multiplying with energy equivalent coefficient and CO2 emission coefficient following standard procedure. Results: Jute-rice-baby corn cropping system recorded significantly higher net energy (324 GJ ha-1) and energy use efficiency (8.02). Among different nutrient and crop management (NCRM) practices, significantly higher energy output (336.9 GJ ha-1) and net energy (291.4 GJ ha-1) recorded 100% NPK with crop residue. The highest carbon footprint recorded with rice-rice (0.44 kg COe kg-1 economic yield) and the lowestwith jute-rice-pea (0.29 kg COe kg-1 economic yield) cropping system. Among different NCRM practices, higher carbon footprint was (0.38 kg COe kg-1 economic yield) recorded with 100% NPK with crop residue. Interpretation: The energy efficient and low input required cropping systems which include legume crops like garden pea and mungbean should be considered for cultivation for diversifying the existing rice-rice cropping system in Eastern India.


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