PENGARUH PLANT GROWTH PROMOTING RHIZOBACTERIA TERHADAP BIOLOGI DAN STATISTIK DEMOGRAFI Thrips parvispinus (THYSANOPTERA: THRIPIDAE) PADA CABAI

2014 ◽  
Vol 5 (2) ◽  
Author(s):  
Rudi Tomson Hutasoit

Plant Growth Promoting Rhizobacteria (PGPR) is a group of bacteria that have been used as a bio-fertilizer to promote the nutrient plants supply and strengthen against plant pests and diseases. The aim of this study is knowing PGPR effect on long bean toward biology and demographic statistic Thrips parvispinus. The study was conducted by observing the development of the Thrips parvispinusfrom eggs to adulton chili pepper leaves with PGPR application or non-PGPR (control). The collected data were used to obtain information about the biology of the pest such as the stadia of each instar, preoviposition period, life cycle, adult longevity and fecundity. The data were also used to construct life tables for demographic statistic analysis using of the Jackknife method. PGPR usage have impact on thebiology of T. parvispinus such aslife cycle, longevity and fecundity. Gross reproduction rate (GRR), net reproductive rate (Ro), and intrinsic rate of increase (r) T. parvispinus with PGPR aplications lower than controls. PGPR can inhibit a doubling time (DT) T. parvispinus becomes longer than controls. Keywords: demographic statistics, life cycle, T. parvispinus

2018 ◽  
Vol 109 (4) ◽  
pp. 479-489 ◽  
Author(s):  
R. Sattari Nasab ◽  
M. Pahlavan Yali ◽  
M. Bozorg-Amirkalaee

AbstractThe cabbage aphid, Brevicoryne brassicae L. (Hem: Aphididae), is an important pest of canola that can considerably limit profitable crop production either through direct feeding or via transmission of plant pathogenic viruses. One of the most effective approaches of pest control is the use of biostimulants. In this study, the effects of humic acid, plant growth-promoting rhizobacteria (PGPR), and integrated application of both compounds were investigated on life table parameters of B. brassicae, and the tolerance of canola to this pest. B. brassicae reared on plants treated with these compounds had the lower longevity, fecundity, and reproductive period compared with control treatment. The intrinsic rate of natural increase (r) and finite rate of increase (λ) were lowest on PGPR treatment (0.181 ± 0.004 day−1 and 1.198 ± 0.004 day−1, respectively) and highest on control (0.202 ± 0.005 day−1 and 1.224 ± 0.006 day−1, respectively). The net reproductive rate (R0) under treatments of humic acid, PGPR and humic acid + PGPR was lower than control. There was no significant difference in generation time (T) of B. brassicae among the tested treatments. In the tolerance test, plants treated with PGPR alone or in integrated with humic acid had the highest tolerance against B. brassicae. The highest values of total phenol, flavonoids, and glucosinolates were observed in treatments of PGPR and humic acid + PGPR. Basing on the antibiosis and tolerance analyses in this study, we concluded that canola plants treated with PGPR are more resistant to B. brassicae. These findings could be useful for integrated pest management of B. brassicae in canola fields.


2017 ◽  
Vol 57 (3) ◽  
pp. 256-267
Author(s):  
Idin Zibaee ◽  
Mojtaba Esmaeily

Abstract The tomato leafminer, Tuta absoluta is a serious pest of tomato crops worldwide. In this study the effect of sublethal concentrations of abamectin (at 10 and 30% lethal concentrations, LC10 and LC30) was investigated on developmental and reproduction parameters of the tomato leafminer Tuta absoluta. Lethal concentrations were estimated by leaf dip bioassay on the fourth instar larvae of the T. absoluta that, LC50, LC30 and LC10 were 0.23, 0.15 and 0.12 mg · l−1, respectively. The sublethal concentrations led to significant decreases in adult emergence, the percentage of pupation of the parent generation, fecundity and adult longevity compared to the control. Sublethal concentrations significantly decreased the net reproductive rate (R0), intrinsic rate of increase (r), finite rate of increase (λ), and gross reproduction rate (GRR). There was a significant decrease in the time to egg developmental and doubling time (DT) of T. absoluta. However, sublethal concentrations of abamectin had no significant effects on the percentage of pupation, larva, prepupa and pupa developmental periods, hatchability and sex ratio of offspring. The results of this study indicated that sublethal concentrations of abamectin could influence some biological parameters of T. absoluta. The results could also be helpful for making better management decisions for controlling the tomato leafminer.


2018 ◽  
Vol 14 (3) ◽  
pp. 107
Author(s):  
Rudi Tomson Hutasoit ◽  
Hermanu Triwidodo ◽  
Ruly Anwar

<p><em>Thrips parvispinus</em> Karny (Thysanoptera: Thripidae) is one of the major pests of chili pepper in Indonesia. The pest<em> </em>can be found on all parts of the plants, especially flowers and leaves. Information of the biology and demographic statistic of <em>T. parvispinus </em>are still limited<em>.</em> The objective of this research was to study the biology and demographic statistic of <em>T</em>. <em>parvispinus </em>in Bogor. Fifty individual of 1<sup>st</sup> instar nymphs were reared on caged chili pepper leaves (d = 4 cm and h = 8 cm). Chilli pepper leaves were replaced everyday and observed daily to determine the development and number of offspring eggs. The collected data were used to obtain information about the biology of the pest such as the stadia of each instar, preoviposition period, life cycle, adult longevity, and fecundity. The data were also used to construct life tables for demographic statistic analysis using of the <em>Jackknife</em> method. There were 5 phases of immature stages of <em>T. parvispinus</em>: eggs, two instars nymph, prepupa, and pupa with their stadia were 4,79, 1,36, 3,54, 1,08, and 1,96 days respectively. The preoviposition period of the insect was 1,11 days, life cycle was 13,68 days, female longevity was 8,55 days, male longevity was 6,00 days, and fecundity was 15,33 eggs per female. The population development of <em>T. parvispinus </em>followed type III of survivorship curve with intrinsic rate of increase was 0,15 individual per days female per days, net reproductive rate was 5,71 individual per female per generation, generation time was 11,49 days and doubling time was 4,57 days.</p>


2016 ◽  
Vol 15 (2) ◽  
pp. 105 ◽  
Author(s):  
Ita Fitriana ◽  
Darmayanti Buchori ◽  
Ali Nurmansyah ◽  
Roschon Ubaidillah ◽  
Akhmad Rizal

Demographic statistic of Diaphania indica Saunders (Lepidoptera: Crambidae). Diaphania indica is a pest of Cucumis sativus L. The information about the biology of D. indica is needed to determine appropriate pest management strategies. The aim of this study was to study the biology and life cycle of D. indica. The study was conducted by observing life stage development of D. indica, such as life cycle, head width and body length. The life table was determined by calculating mortality of D. indica individuals and fecundity at each age. Mortality and fecundity data of D. indica were then used to calculate the parameters of population growth including gross reproduction rate (GRR), net reproductive rate (Ro), mean generation time (T) and and intrinsic rate of increase (r ). The results show that the life cycle of D. indica is about 25.7 days, while egg stadium = 3.2 days, larval stadium = 13.5 days, pupal stadium = 7.9 days, imago stadium = 8.6 days, and preoviposition period = 3.9 days. GRR of D. indica is 263 individuals per generation. Ro = 51 individuals per female per generation. T is 31.3 days and the innate capacity for increase (r) = 0.1 individual per female per day.


2020 ◽  
Vol 21 (1) ◽  
pp. 14-19
Author(s):  
Praptiningsih Gamawati Adinurani ◽  
Sri Rahayu ◽  
Nurul Fima Zahroh

Mikroba Bacillus subtilis merupakan agen pengendali hayati mempunyai kelebihan sebagai Plant Growth Promoting Rhizobacteria (PGPR) yaitu dapat berfungsi sebagai biofertilizer, biostimulan, biodekomposer dan bioprotektan. Tujuan penelitian mengetahui potensi B. subtilis dalam merombak bahan organik sebagai usaha meningkatkan ketersediaan bahan organik tanah yang semakin menurun. Penelitian menggunakan Rancangan Petak Terbagi dengan berbagai  bahan organik sebagai petak utama (B0 = tanpa bahan organik, B1 = kotoran ayam,  B2 = kotoran kambing, B3 = kotoran sapi) dan aplikasi B.subtilis sebagai anak petak (A0 = 0 cc/L, A1 = 5cc/L, A2 = 10 cc/L, Pengamatan meliputi variabel tinggi tanaman, indeks luas daun, jumlah buah per tanaman, berat buah per tanaman, dan bahan organik tanah. Data pengamatan  dianalisis ragam  menggunakan  Statistical Product and Service Solutions (SPSS) versi 25 dan dilanjutkan dengan uji Duncan untuk mengetahui signifikansi perbedaan antar perlakuan. Hasil penelitian menunjukkan tidak terdapat interaksi antara bahan organik kotoran ternak dan konsentrasi B. subtilis terhadap semua variabel pengamatan. Potensi B. subtilis sangat baik dalam mendekomposisi bahan organik yang ditunjukkan dengan peningkatan bahan organik, dan hasil terbaik pada kotoran  sapi (B3) dan konsentrasi B. subtilis 15 mL/L masing-masing sebesar 46.47 % dan 34.76 %. Variabel pertumbuhan tidak berbeda nyata kecuali tinggi tanaman dengan pertambahan tinggi paling banyak pada pemberian kotoran kambing sebesar 170.69 %.


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