Evaluation of Some Botanical Extracts Against Major Insect Pests (Leafminer, Armored scale and Woolly Whitefly) of Citrus Plants in Central Zone of Tigray, North Ethiopia

Citrus fruit production is suffering from various yield-limiting factors particularly the sucking pests viz, citrus leafminer Phyllocnistis citrella, woolly whitefly, Aleurothrixus floccosus and scale insects especially armored scales Aonidiella auriantii. The present paper tries to identify the effective botanical insecticides against these insect pests on citrus orange. An experiment was conducted in the established citrus orange farm in Kolla Temben at two farmer’s fields, Adiha and Agibe during the off-season of 2018 under irrigation growing condition in a randomized complete block design with six treatments and replicated thrice. The findings in both experimental sites showed that the neem seed extract had a significantly (P=0.001) lower leafminer infestation levels compared to the untreated control which is on par to the insecticide treatment of dimethoate. On the other hand, in both areas, whitefly mortality of more than 81% on average was recorded from neem seed extract followed by Tree tobacco (70%) (P=0.001). For scale insects however, in both experimental sites, the highest mean percent mortality was recorded from the insecticide dimethoate 40% EC (86.9%, 87.2 & 86.0%on average) followed by neem seed and tree tobacco extracts,70.1 and 65.4% respectively. The botanicals particularly the neem seed extracts followed by tree tobacco are as effective as the chemical insecticide, dimethoate 40% EC, even superior in some cases, in controlling the target pests. Therefore, these botanicals could be used as an IPM component for against the target pests.

Aktivitas Penolak Serangga (Insect Repellent) Ekstrak Klorofom Biji Mimba (Azadirachta Indica) Terhadap Kutu Beras (Calandra Oryzae)

Plants that are currently being developed as botanical insecticides are those that produce essential oils. The largest active compound that is insecticidal in neem (Azadirachta indica) is azadirachtin, this compound belongs to the triterpenoid group. The purpose of this study was to determine the level of insect repellent activity of neem (Azadirachta indica) seed chlorophome extract against rice lice (Calandra oryzae). This research is an experimental study using a completely randomized design (CRD). Consisting of neem seed extract treatment with a concentration of 0.1% and 0.5% and a control in the form of distilled water each 10 times. The results of this study indicated that the concentration of 0.1% and 0.5% neem seed extract test increased the mortality of rice lice. The longer the application time, the higher the mortality rate of rice lice. In the treatment of 0.5% neem seed extract, it could cause 67% mortality compared to 0.1% neem seed extract treatment and control. Keywords: Neem seeds, insect repellent, Calandra oryzae ABSTRAK Tumbuhan yang saat ini sedang dikembangkan sebagai insektisida nabati yaitu tumbuhan yang menghasilkan minyak atsiri. Senyawa aktif terbesar yang bersifat insektisida pada tanaman mimba (Azadirachta indica) adalah azadirachtin, senyawa ini termasuk dalam kelompok triterpenoid. Tujuan dari penelitian ini yaitu untuk mengetahui tingkat aktivitas penolak serangga (insect repellent) ekstrak klorofom biji mimba (Azadirachta indica) terhadap kutu beras (Calandra oryzae). Penelitian ini merupakan penelitian eksperimental yang menggunakan Rancangan Acak Lengkap (RAL). Terdiri atas perlakuan ekstrak biji mimba konsentrasi 0.1% dan 0.5 % dan kontrol berupa akuades masing-masing 10 kali ulangan. Hasil penelitian ini menunjukkan bahwa Uji ekstrak biji mimba konsentrasi 0.1% dan 0.5% meningkatkan mortalitas kutu beras. Semakin lama waktu aplikasi maka semakin tinggi tingkat mortalitas kutu beras. Pada perlakuan ekstrak biji mimba 0.5% dapat menyebabkan kematian sebesar 67% dibandingkan dengan perlakuan ekstrak biji mimba 0.1% dan kontrol. Kata Kunci: Biji Nimba, penolak serangga, Calandra oryzae

Use of Natural Nitrogen Stabilizers to Improve Nitrogen use Efficiency and Wheat Crop Yield

Complex nature of nitrogen fertilizer in soil and poor management practices are major causes of low fertilizer use efficiency in Pakistan. These factors further increases nitrogen losses in form of nitrate leaching and volatilization of ammonium, as well as nitric oxide which are burning economic and environmental threats. Keeping in view the demand of urea application in Pakistan and its low efficiency, we hypothized that appropriate urea management with neem formulations or biofertilizers can enhance the nitrogen use efficiency. We designed experiment with treatments: T0 (N0 application), T1 (recommended nitrogen), T2 (recommended nitrogen + biofertilizer), T3 (recommended nitrogen + neem seed extract), T4 (75% recommended nitrogen + biofertilizer), T5 (75% recommended nitrogen + neem seed extract), T6 (recommended nitrogen + biofertilizer + neem seed extract), T7 (75% recommended nitrogen + biofertilizer + neem seed extract) in wheat crop. The experiment was laid out in randomized complete block design (RCBD) with split plot arrangements. Different approaches for stabilized nitrogen fertilizer responded significantly for the wheat plant height, tillers per plant, number of grains per spike, 1000-grain yield, grain yield and harvest index. Result exhibited that wheat crop enhanced yield attributes and finally the yield under treatment T6 and T7 for both wheat cultivars. Treatments comparison with recommended nitrogen (T1) revealed that all treatments with biofertilizer, as well as with neem seed, enhanced crop performance along with nitrogen use efficiency. It can be concluded that nitrogen fertilizer can be stabilized in the soil with the use of different natural products for sustainable crop production.

Effect of aqueous neem seed extract via irrigation on larvae of Liriomyza sativae in melon crop

ABSTRACT The leafminer [Liriomyza sativae (Diptera: Agromyzidae)] is one of the main pests of melon crop (Cucumis melo) in the states of Rio Grande do Norte and Ceará. Thus, adopting strategies to control this destructive insect is essential. The aim of this study was to evaluate the effect of aqueous neem seed extract, applied to soil via irrigation, on leafminer larvae, in the melon crop. An experiment was conducted in greenhouse, in completely randomized design, consisting of five treatments (four doses of aqueous neem seed extract: 1; 3; 5 and 10 g/100 mL) and the control consisting only of distilled water and 10 replicates (melon plants). The treatments were applied in a single dose, via soil irrigation. In the first stage of the evaluation, 24 hours after application, the number of dead larvae per plant was counted. In the second step, pupal mortality was recorded. The total mortality was also calculated considering the number of larvae and the number of emerged adults. We verified that, increasing the concentration of aqueous neem seed extract, an increase in the larval and pupal mortality of the leafminer in melon crop was noticed. The concentration 10 g/100 mL presented the best results, resulting in 36.4% of larval mortality, 96.5% of pupal mortality and 96.8% of total mortality.

Efficacy and safety of neem seed extract compared with clotrimazole in tinea corporis/ cruris: A randomized controlled trial

Introduction: Tinea corporis and tinea cruris are common superficial fungal infections. Neem (Azadirachta indica) seed extract has shown antifungal properties in vitro, but no clinical studies have been done for superficial dermatophytoses. This study compared the efficacy and safety of 5% neem seed extract in cream base with 1% clotrimazole cream when used twice daily for four weeks, in the treatment of localized tinea corporis and/or tinea cruris.Materials and Methods: This is a randomized, double blind, clinical trial. Patients with localized tinea corporis and/or tinea cruris were evaluated at baseline, week 1, week 2 and week 4. Clinical, mycological and effective cure rates of both treatment groups were determined. The patients’ post treatment overall satisfaction scores and the incidence of adverse effects were also documented.Results: Sixty patients were recruited, and 30 patients were randomized to each treatment arm. There were no significant differences in post treatment scores (p value=0.221). Effective cure, defined as the combination of marked clinical improvement and mycological cure, was seen in 20/30 (66.67%) in the neem seed extract group and 24/30 (80%) in the clotrimazole group (relative risk = 1.67, 95% confidence interval = 0.69 – 4.0). Post treatment overall satisfaction scores were comparable (p value = 0.333). Two patients experienced adverse effects in the neem seed extract group, while there were no adverse effects in the clotrimazole group.Conclusion: Efficacy and safety of 5% neem seed extract in cream base is comparable to 1% clotrimazole cream for the treatment of localized tinea corporis and/or tinea cruris.

Brokkoli Tohumlarına Uygulanan Bazı Organik Asit ve Bitkisel Kökenli Materyallerin Çimlenme, Çıkış ve Fide Kalitesine Etkisi

The research was carried out to investigate the effect of plant materials which are used as an alternative to synthetic chemicals in organic agriculture (thyme, mint, basil and garlic oil, hot pepper, and neem tree seed extract) and some organic acids (salicylic and jasmonic acid) on the germination, emergence, and seedling traits in broccoli (Brassica oleracea var. italica) cv. Jade. The seeds of broccoli treated with these materials were subjected to germination and emergence tests at 20±1°C and 60±5% RH in autumn period. After that, all seeds (including untreated) were kept at 5±1°C and again evaluated for germination, emergence, and seedling traits in spring period. In spring period, the seeds treated with neem seed extract gave highest germination percentage (91.75%). Also, they germinated in shortest time (3.80 days). The lowest germination/emergence percentage and highest mean germination/emergence time was obtained from the seeds treated with thyme oil in both periods. The seeds treated with basil oil had the higher infected seedlings than others. There were no significant differences among treatments in term of seedling traits (except leaf number).