scholarly journals Biological Activity of Ajuga iva Extracts against the African Cotton Leafworm Spodoptera littoralis

2020 ◽  
Author(s):  
Leena Taha-Salaime ◽  
Galina Lebedev ◽  
Jackline Abo-Nassar ◽  
Sally Marzouk ◽  
Moshe Inbar ◽  
...  
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Relative Growth Rate ◽  
Spodoptera Littoralis ◽  
Leaf Extract ◽  
Aqueous Suspension ◽  
Larval Weight ◽  
Relative Growth ◽  
Cotton Leafworm ◽  
Crude Leaf Extract

Control of the crop pest African cotton leafworm Spodoptera littoralis (Boisduval) by chemical insecticides has led to serious resistance problems. Ajuga plants contain phytoecdysteroids (arthropod steroid hormone analogs regulating metamorphoses) and clerodanes (diterpenoids exhibiting antifeedant activity). We analyzed these compounds in leaf extracts of the Israeli Ajuga iva L. by LC-TOF-MS and TLC, and their efficiency at reducing S. littoralis fitness. First and third instars of S. littoralis larvae were fed on castor bean leaves smeared with an aqueous suspension of dried methanolic crude extract of A. iva phytoecdysteroids and clerodanes. Mortality, larval weight gain, relative growth rate and survival were compared to feeding on control leaves. We used DAPI and phalloidin staining to localize A. iva crude leaf extract activity in the insect gut. A. iva crude leaf extract (50, 100 and 250 µg/µL) significantly increased mortality of first-instar S. littoralis larvae (36%, 70% and 87%, respectively) compared to controls (6%). Third-instar larval weight gain decreased significantly (by 52%, 44% and 30%, respectively), as did relative growth rate (–0.05 g/g per day compared to the relevant controls), ultimately resulting in few survivors. Crude leaf extract (250 µg/µL) reduced gut size, with relocation of nuclei and abnormal actin-filament organization. A. iva extract has potential for alternative, environmentally safe insect-pest control.

scholarly journals Activity of Ajuga iva Extracts Against the African Cotton Leafworm Spodoptera littoralis

Insects ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 726
Author(s):  
Leena Taha-Salaime ◽  
Galina Lebedev ◽  
Jackline Abo-Nassar ◽  
Sally Marzouk ◽  
Moshe Inbar ◽  
...  
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Relative Growth Rate ◽  
Spodoptera Littoralis ◽  
Leaf Extract ◽  
Aqueous Suspension ◽  
Larval Weight ◽  
Relative Growth ◽  
Cotton Leafworm ◽  
Crude Leaf Extract

Control of the crop pest African cotton leafworm, Spodoptera littoralis (Boisduval), by chemical insecticides has led to serious resistance problems. Ajuga plants contain phytoecdysteroids (arthropod steroid hormone analogs regulating metamorphosis) and clerodanes (diterpenoids exhibiting antifeedant activity). We analyzed these compounds in leaf extracts of the Israeli Ajuga iva L. by liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) and thin-layer chromatography (TLC), and their efficiency at reducing S.littoralis fitness. First and third instars of S. littoralis were fed castor bean leaves (Ricinus communis) smeared with an aqueous suspension of dried methanolic crude extract of A. iva phytoecdysteroids and clerodanes. Mortality, larval weight gain, relative growth rate and survival were compared to feeding on control leaves. We used ‘4’,6-diamidino-2-phenylindole (DAPI, a fluorescent stain) and phalloidin staining to localize A. iva crude leaf extract activity in the insect gut. Ajuga iva crude leaf extract (50, 100 and 250 µg/µL) significantly increased mortality of first-instar S. littoralis (36%, 70%, and 87%, respectively) compared to controls (6%). Third-instar larval weight gain decreased significantly (by 52%, 44% and 30%, respectively), as did relative growth rate (−0.05 g/g per day compared to the relevant controls), ultimately resulting in few survivors. Crude leaf extract (250 µg/µL) reduced gut size, with relocation of nuclei and abnormal actin-filament organization. Ajug iva extract has potential for alternative, environmentally safe insect-pest control.

scholarly journals Biological activity of Ajuga iva extracts against the African cotton leafworm Spodoptera littoralis

2020 ◽  
Author(s):  
Leena Taha-Salaime ◽  
Galina Lebedev ◽  
Jackline Abo-Nassar ◽  
Sally Marzouk ◽  
Moshe Inbar ◽  
...  
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Relative Growth Rate ◽  
Crude Extract ◽  
Spodoptera Littoralis ◽  
Leaf Extract ◽  
Larval Weight ◽  
Relative Growth ◽  
Crude Leaf Extract ◽  
Insect Gut

AbstractThe African cotton leafworm Spodoptera littoralis, a major crop pest worldwide, is controlled by chemical insecticides, leading to serious resistance problems. Ajuga plants contain phytoecdysteroids (analogs of arthropod steroid hormones that regulate metamorphoses) and clerodanes (diterpenoids exhibiting antifeedant activity). We analyzed phytoecdysteroids and clerodanes in leaf extracts of the Israeli Ajuga iva by LC-TOF-MS and TLC, and their efficiency at reducing S. littoralis fitness. Castor bean leaves were smeared with an aqueous suspension of dried methanolic crude extract of phytoecdysteroid and clerodanes from A. iva leaves (50, 100 and 250 µg/µl). First and third instars of S. littoralis larvae were fed with 1 treated leaf for 3 and 4 days, respectively. Mortality, larval weight gain, relative growth rate and survival were compared to feeding on control leaves. To evaluate and localize A. iva crude leaf extract activity in the insect gut, we used DAPI and phalloidin staining. Crude extract of A. iva leaves (50, 100 and 250 µg/µl) significantly increased mortality of first instar S. littoralis larvae (36%, 70% and 87%, respectively) compared to controls (6%). Third instar larval weight gain decreased significantly (by 52%, 44% and 30%, respectively), as did relative growth rate (–0.05 g/g day, compared to the relevant controls). S. littoralis larvae were further affected at later stages, with few survivors. Insect-gut staining showed that 250 µg/µl crude leaf extract reduces gut size, with relocation of nuclei and abnormal actin-filament organization. Our results demonstrate the potential of A. iva extract for alternative, environmentally safe insect-pest control.Key MessageInsects cause severe damage to numerous crops and their control relies on pesticides. Green control is becoming increasingly popular due to concerns about the negative impacts of pesticides on the environment. Phytoecdysteroids are found in Ajuga plants and affect a wide range of insects at very low concentrations. Here we demonstrate that crude extract from Ajuga iva alters the development of Spodoptera littoralis. Phytoecdysteroids may therefore be beneficial in IPM programs.

scholarly journals Live weight dynamics and exterior indexes of jersey breed fed on dry brewers waste

2019 ◽  
pp. 95-102
Author(s):  
A. Veres ◽  
M. Kryvyi
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Relative Growth Rate ◽  
Live Weight ◽  
The Body ◽  
Daily Weight Gain ◽  
Control Group ◽  
Average Daily Weight Gain ◽  
Relative Growth ◽  
Experimental Group

The scientific results of the body weight dynamics, the multiplicity of its increase, the average daily weight gain, the relative growth rate and the exterior indicators are presented. The brewers waste is a high-protein product with a high content of carbohydrates, including fiber.For the research, three groups of Jersey breed were formed on the principle of the analogue group: the first was control, the second and the third – experimental. Their rations were introduced by 15 % and 20 % of dry brewers waste from the total diet, respectively. It was established that the live weight of the experimental cows from the 2nd group was 9.3 times bigger. The live weight of the experimental cows from the 1st and 3rd group increased 9 times. The cows from the 2nd group had the highest average daily weight gain (811.4 g) in the period from 2 to 6 months. It was 3.2 % times more than in the control group and 7.4 % times more than in the 3rd experimental group. The cows from the 2nd experimental group had the highest relative growth rate (85.7 %) in the period from 2 to 6 months which was 2.2 % times more than in the 1st control group and 4.2% times more than in the 3rd experimental group. In the period from 6 to 12 months, the 2nd experimental group had the highest average daily weight gain (671.4 g), which was 2.1 % more than in the 1st control group and 3.5 % more than in the 3rd experimental group. From 6 to 12 months the relative growth rate in all groups was almost the same and ranged from 54.2% – 54.7 %. At the age of 12 months, the 1st control group had greater index (120.4). The 3rd experimental group had 119.6 and the 2nd – 118.6. The 2nd group of the same age had better shooting index than the 1st control group 0.7 % times more and the 3rd group 1.4 % times more. It indicated the better development of the body weight. Key words: dynamics, weight gain, repair heifers, Jersey breed, measurements, indicators.

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