Eliciting increased flavonoids content in Ginkgo biloba leaves through exogenous salicylic acid and methyl jasmonate treatments

Prior to Ginkgo leaf harvest, we implemented four exogenous applications of salicylic acid (SA: 50, 80, and 100 mg·L−1) or methyl jasmonate (MJ: 20, 40, and 80 mg·L−1) as leaf spray to investigate their effect on flavonoids content and related enzyme activity. Compared with the control, a significant increase of 12% and 26% in flavonoid content was observed 7 days after the first application of 100 mg·L−1 SA and 20 mg·L−1 MJ, respectively; both were determined to be the best treatments. Operationally, administering either elicitor (SA or MJ) 1 week prior to leaf harvest is deemed to be the most practical and economic option. Additionally, enzymes activity involved in flavonoid metabolism (phenylalanine ammonia-lyase, cinnamate 4-hydroxylase, and 4-coumarate:coenzyme A ligase) and antioxidants (peroxidase, superoxide dismutase, and catalase) significantly increased in most SA and MJ treatments. The results strongly support Ginkgo leaf response to SA- or MJ-induced stress through increased nonenzymatic antioxidant compounds (flavonoids) and activity of antioxidant enzymes.

Response of hemp (Cannabis sativa L.) to integrated application of chemical and manure fertilizers

<p>The investigation of various nutrition systems in hemp plays an influential role in improving its production. An experiment was conducted in University of Birjand, Iran, during 2013-2014, in which manure (0, 10, 20, and 30 t.ha-1 of cow manure) was considered as the main plot and the combination of nitrogen (0, 50, and 100 kg N ha-1 as urea) with phosphorus (0 and 80 kg P ha-1 as triple superphosphate) fertilizers was considered as factorial in subplots. The type of soil fertility management had no significant effect on the percentage of female plants. Applying 20 t.ha-1 of manure plus 100 kg N ha-1 produced the highest biological yield, seed, and leaf extract. The highest oil content was obtained by applying a maximum of 50 kg N ha-1 without the use of phosphorus. The 30 t ha-1 manure plus 100 kg N ha-1 increased the leaf harvest index and decreased seed harvest index. Nitrogen consumption also increased the seed oil content and yield. Phosphorus increased the biomass and extracts of seed and leaves, also biological, seeds and oil yield. It seems hemp responds well to the combined application of nitrogen fertilizer and animal manure, while its response to P fertilization was limited. </p>

Leaf and roots yields responses of three improved cassava (Manihot esculenta Crantz) varieties to organo-mineral fertilizers and leaf harvest in the South-West Nigeria

L’étude a été menée dans l’objectif d’évaluer la production de trois variétés améliorées de manioc en réponse à la récolte des feuilles et aux fertilisants NPK, compost et Compost-NPK. L’essai a été fait selon le dispositif en split-split plot, à blocs aléatoires complets à trois facteurs et trois réplications. Les récoltes ont été réalisées à 3 mois et 5 mois après la plantation. La récolte finale a été faite à 12 Mois Après la Plantation (MAP). Le résultat montre qu’une différence non significative (p>0,05) a été observée entre les variétés et entre les traitements fertilisants du rendement en feuilles sèches total. La moyenne totale du rendement en feuilles sèches s'élève à 1454,19 kg/ha au niveau du contrôle. Et ce rendement augmente en moyenne de 10,42% en présence du compost, 39,91% quand le mélange Compost-NPK a été appliqué et de 34, 19% en présence de NPK. Le rendement racinaire varie significativement (p˂0,05) en fonction des variétés et traitement de récolte des feuilles. La perte moyenne de rendement sec due à la récolte des feuilles est de 3,86 t/ha soit 45,77%. La perte du rendement racinaire sec a été compensée en moyenne de 35,59% soit 1,64 t/ha par le mélange Compost-NPK, et 24,05% soit 1,11 t/ha quand le NPK a été appliquée. Parmi les variétés, deux répondent aux fertilisants et sont capables de compenser les pertes. L’IITA-TMS-IBA071393 serait un bon candidat pour les petits exploitants dépourvus de moyen d’intrant.Mots clés : Génotypes de manioc, cueillette des feuilles, engrais organo-minéral, rendement, effet compensatoire. English Title: Leaf and roots yields responses of three improved cassava (Manihot esculenta Crantz) varieties to organo-mineral fertilizers and leaf harvest in the South-West NigeriaThis study was carried out to investigate the leaf and root yield response to leaf harvest and the application of NPK fertilizer, compost and the combination of NPK plus compost of three improved cassava varieties. The experiment was a complete randomised split-split plot design with three factors and three replications. Leaf harvest was at 3 months and 5 months after planting (MAP). The final root harvest was at 12 MAP. The leaf dry matter yield was not significantly (p> 0.05) different between varieties and fertilizer treatments. The average leaf yield was 1454.19 kg/ha DM in control. Leaf yield increased by 10.42% when compost was applied, by 39.91% when compost plus NPK was applied and by 34.19% when only NPK was applied. Root yield was significantly (p˂0.05) affected by cassava variety and leaf harvest. Average root DM yield losses were 3.86 t/ha (45.77%) when leaves were harvested. Root DM yield loss was compensated to 35.59% (1.64 t/ha) when compost plus NPK fertilizer was applied and 24.05% (1.11 t/ha) when NPK was applied. Two varieties responded positively to fertilisers and were able to compensate for root yield losses. IITA-TMS-IBA071393 appears a suitable candidate for cassava farmers with small income because it did not require inputs. Keywords: Cassava genotypes, leaves harvesting, organo-mineral input, yield, compensation effect.

Light Interception and the Growth of Pastures under Ideal and Stressful Growing Conditions on the Allegheny Plateau

Pasture-based livestock production is impacted by management and weather. In pastures, there is conflict between leaf retention for plant growth and leaf harvest for animal nutrition. Defoliated pastures with low light interception (LI) may have a low forage growth rate (FGR), while excessive growth shades leaves, reducing FGR and resulting in an S-shaped regrowth curve. To optimize production, it is best to keep FGR linear. Three studies were conducted to evaluate the impact of management and weather on FGR. Replicated pastures were used to measure FGR when grazed from 25 to 10 cm and allowed to regrow. The impact of alternative defoliation timings and intensities on FGR were studied using clipped treatments at three recovery intervals and two stubble heights. Variability in FGR was studied using a field validated plant growth model. Of the 24 growth periods studied, two displayed exponential, 12 linear and 10 linear-plateau growth. There was no effect of FM on growth curve form. In May and June, LI increased with canopy height, up to 0.93. Stubble height and days of growth impacted FGR with an interaction. There was no treatment impact on root density. Weather caused variation in FGR. A low FGR risk occurs at high elevations; greater risk occurs east of the plateau.