DENSITY AND PUPATION SITE OF APTEROUS FEMALE BAGWORMS, METISA PLANA (LEPIDOPTERA: PSYCHIDAE), INFLUENCE THE DISTRIBUTION OF EMERGENT LARVAE

1998 ◽  
Vol 130 (5) ◽  
pp. 603-613 ◽  
Author(s):  
Marc Rhainds ◽  
Gerhard Gries ◽  
Ahmad Saleh

AbstractIn an oil palm plantation in northeast Sumatra, Indonesia, we tested the hypotheses that selection of pupation site by female bagworms, Metisa plana (Walker), influences the distribution of emergent larvae, and that intertree dispersal by larvae is density dependant. Similar intratree distributions of empty female pupal cases and early instars and significant regressions between numbers of female pupal cases and larvae per leaf for 36 out of 39 palms indicated that larvae generally remain on the same leaf where they emerged. Proportions of early instars per female pupal case decreased with increasing densities of female pupal cases per tree and were greater on trees surrounding most heavily infested palms, suggesting that intertree dispersal of early instars is density dependent. Interspecific comparisons of life history constraints between M. plana and the allopatric bagworm Oiketicus kirbyi (Guilding) reveal different selective pressures that may have converged and favoured the development of an identical life history trait.

2017 ◽  
Vol 20 (2) ◽  
pp. 51-58
Author(s):  
Latifa Siswati ◽  
M Rizal

The aim of this study was to reveal the increase of farmer family income at oil palm plantation and dairy farm in supporting the comodity of plantation in Indonesia especially Riau Province. Survey method was applied in this study in which the samples were collected as the purposive sampling. Result of the experiment showed that integratiob system of raising cow within oil palm plantation might have a good petency in supporting the development of the oil palm plantation. Cows would provide organc fertilizer and improve the soil tecture and this integration system could reduce the production cost. Selection of farmer could be based on location determination, program socialisation, participative plan, development activity and evaluation of program. This program could contribute to the farmer income that could be an alternative side income  especially during low oil palm price. The farmer income  was around  Rp 3.600.000 ha-1 farmer-1 from at oil palm plantation and Rp 4.819,500,- month-1 farmer-1. The total farmer income was around Rp 8.419,500,-


SIMBIOSA ◽  
2014 ◽  
Vol 3 (1) ◽  
Author(s):  
Fauziah Syamsi

Kelapa sawit merupakan salah satu tanaman meningkat paling pesat di dunia, dan mencakup lebih dari 13 juta ha di Asia Tenggara. Sumatera memiliki sejarah yang relatif panjang budidaya kelapa sawit komersial, dan banyak perkebunan telah menggantikan hutan hujan. Biasanya ini perkebunan monokultur mendukung spesies lebih sedikit daripada hutan, namun ada sangat sedikit informasi yang tersedia untuk kelelawar. Kami mencicipi kelelawar pemakan serangga di Sumatera Barat dalam perkebunan kelapa sawit matang di mana beberapa tutupan hutan dipertahankan di fragmen hutan di bukit-bukit dan di sepanjang sungai. Menggunakan total 180 kecapi perangkap malam kami dibandingkan dengan komunitas kelelawar dalam tiga jenis habitat: patch hutan, zona riparian dan perkebunan. Total kami ditangkap 1108 kelelawar yang mewakili 21 spesies dan 5 keluarga, dan mayoritas ini (dalam hal spesies dan kelimpahan) ditemukan di fragmen hutan. perkebunan kelapa sawit ditemukan menjadi habitat miskin untuk kelelawar - hanya empat orang dari dua spesies ditangkap. daerah pinggiran sungai didukung keanekaragaman menengah, dan mungkin penting sebagai koridor satwa liar antara fragmen hutan. Kata kunci : Biodiversitas, keleawar Microchiropteran


2009 ◽  
Vol 2 (2) ◽  
pp. 209-228 ◽  
Author(s):  
Leslie Rebecca Bloom ◽  
Amanda Reynolds ◽  
Rosemary Amore ◽  
Angela Beaman ◽  
Gatenipa Kate Chantem ◽  
...  

Readers theater productions are meaningful expressions of creative pedagogy in higher education. This article presents the script of a readers theater called Identify This… A Readers Theater of Women's Voices, which was researched, written, and produced by undergraduate and graduate students in a women's studies class called Intersections of Race, Class, and Gender. Section one of the article reproduces the script of Identify This that was based on life history interviews with a diverse selection of women to illustrate intersectional identities. Section two briefly describes the essential elements of the process we used to create and perform Identify This.


2020 ◽  
Vol 7 (1) ◽  
pp. 21
Author(s):  
Faradina Marzukhi ◽  
Nur Nadhirah Rusyda Rosnan ◽  
Md Azlin Md Said

The aim of this study is to analyse the relationship between vegetation indices of Normalized Difference Vegetation Index (NDVI) and soil nutrient of oil palm plantation at Felcra Nasaruddin Bota in Perak for future sustainable environment. The satellite image was used and processed in the research. By Using NDVI, the vegetation index was obtained which varies from -1 to +1. Then, the soil sample and soil moisture analysis were carried in order to identify the nutrient values of Nitrogen (N), Phosphorus (P) and Potassium (K). A total of seven soil samples were acquired within the oil palm plantation area. A regression model was then made between physical condition of the oil palms and soil nutrients for determining the strength of the relationship. It is hoped that the risk map of oil palm healthiness can be produced for various applications which are related to agricultural plantation.


2016 ◽  
Vol 24 (1) ◽  
pp. 39-46
Author(s):  
Winarna Winarna ◽  
Iput Pradiko ◽  
Muhdan Syarovy ◽  
Fandi Hidayat

Development of oil palm plantation on peatland was faced with hydrophobicity problem caused by over drained. Hydrophobicity could reduce water retention and nutrient availability in the peat soil. Beside of proper water management application, addition of soil ameliorant which contain iron could increase stability and improve peat soil fertility. The study was conducted to obtain the effect of steel slag on peat soil properties and hydrophobicity. In this study, peat soil was incorporated with steel slag and incubated in 60 days period. The research was employed completely randomized design (CRD) factorial 2 x 2 x 4. First factor is peat maturity consists of two levels: sapric (S) and hemic (H), while the second factor is soil moisture which also consist of two levels: field capacity (W1) and dry (under the critical water content) (W2). The third factor is steel slag dosage which consist of four levels: 0 g pot (TB0), 7.17 g pot (TB1), 14.81 g -1 -1 pot (TB2), and 22.44 g pot (TB3). The result showed that application of steel slag significantly increase of soil pH, ash content, and water retention at pF 4.2. Furthermore, application of steel slag significantly reduce time for water reabsorption (wettability) in sapric. On the other hand, there are negative corellation between water penetration and soil pH, ash content, and water retention at pF 4.2. Overall, application of steel slag could increase wettability and prevent peat soil hydrophobicity.


2017 ◽  
Vol 25 (3) ◽  
pp. 171-182
Author(s):  
Rizki Amalia ◽  
Ratnawati Nurkhoiry ◽  
Zulfi Prima Sani Nasution ◽  
Ambar Kurniawan

The study of replanting models for smallholding oil palm plantation analysis is focus on smallholders and cooperatives' readiness assessment involves in replanting and business development program. The research objects are four oil palm plantantion cooperatives (KPS) in Ophir, West Pasam: KPS Perintis, KPS Indah, KPS Maju and KPS Makmur. Smallholders readiness in replanting and business development program was assessed through three criterias, which are ability to repay of debt, good faith to join community, and cooperative capacity. The results showed that smallholders in KPS Ophir are basically ready and feasible in obtaining financing and follow the oil palm replanting program, but access to financing and regulations that requires avalis become constrains for the smallholders.


2021 ◽  
Author(s):  
Anik Dutta ◽  
Fanny E. Hartmann ◽  
Carolina Sardinha Francisco ◽  
Bruce A. McDonald ◽  
Daniel Croll

AbstractThe adaptive potential of pathogens in novel or heterogeneous environments underpins the risk of disease epidemics. Antagonistic pleiotropy or differential resource allocation among life-history traits can constrain pathogen adaptation. However, we lack understanding of how the genetic architecture of individual traits can generate trade-offs. Here, we report a large-scale study based on 145 global strains of the fungal wheat pathogen Zymoseptoria tritici from four continents. We measured 50 life-history traits, including virulence and reproduction on 12 different wheat hosts and growth responses to several abiotic stressors. To elucidate the genetic basis of adaptation, we used genome-wide association mapping coupled with genetic correlation analyses. We show that most traits are governed by polygenic architectures and are highly heritable suggesting that adaptation proceeds mainly through allele frequency shifts at many loci. We identified negative genetic correlations among traits related to host colonization and survival in stressful environments. Such genetic constraints indicate that pleiotropic effects could limit the pathogen’s ability to cause host damage. In contrast, adaptation to abiotic stress factors was likely facilitated by synergistic pleiotropy. Our study illustrates how comprehensive mapping of life-history trait architectures across diverse environments allows to predict evolutionary trajectories of pathogens confronted with environmental perturbations.


Sign in / Sign up

Export Citation Format

Share Document