Physiological responses of photosynthesis in black pepper plants under different shade levels promoted by intercropping with rubber trees

Abstract

Plants of black pepper (Piper nigrum L.) may display changes in their photosynthetic activity as a result of environmental seasonal changes. Intercropping with tree species may represent an alternative to mitigate the impacts of climatic changes on crops. The objective of this work was to evaluate the physiological responses of photosynthesis in black pepper plants under different shade levels promoted by intercropping with rubber trees (Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg. The photosynthetic performance in black pepper along the day was evaluated under full sun and five shade levels. The resulted showed that variations positives in leaf gas exchanges were not exclusively dependent on the shade promoted by the distance in relation with the line of rubber trees in the field, but also fluctuate depending on the period of the day, the orientation (Northern or Southern), relating the line of trees and the season of the year. This study showed that shaded intercropped plants displayed some advantage in a few cases (black pepper plants located at 2 m, and 5 m between rubber trees, southern side) as regards the photosynthetic rate at midday and afternoon, and especially in summer, when compared to pepper plants cultivated in full sunlight condition, That would be likely related to the to the maintenance of somewhat lower temperature and higher relative humidity in the atmosphere close to the black pepper plant implying some advantage for such consortium system to mitigate the possible effects of future climate changes, like warming.

Growth of Ornamental Pepper in Colored Containers Under Protected Environments

“…Protected environments influenced the most variables; there was a difference among the containers only for plant height at 30 DAT, stem diameter at 15 and 30 DAT, and number of flowers at 90 DAT ( Table 2). The shading levels of the protected environment affected pepper cultivation more than the color of pots, as greater shading favored growth, development, and production of the plants, in agreement with Zhu et al (2012) and Oliveira et al (2018), who had verified that this species adapted better in shaded environments. TABLE 2.…”

Morphophysiological changes in black pepper under different water supplies

“…Besides, other factors, this behavior can be explained by photoassimilate production reductions (Tatagiba, Pezzopane, & Reis, 2015) due to stomatal closure under water deficit conditions (Peloso, Tatagiba, & Amaral, 2017), limiting vegetative crop growth. This could be observed in various crops such as black pepper (Piper nigrum), bell pepper (Capsicum annuum), lilac (Syringa oblata), and euonymus (Euonymus japonicus) (Oliveira, Oliosi, Partelli, & Ramalho, 2018;Sui, Mao, Wang, Zhang, & Zhang, 2012;Wu, Chow, Liu, Shi, & Jiang, 2014). Our results demonstrate that the water irrigation volume applied to meet crop water needs (100% by SIC) favored black pepper growth.…”

Nitrogen effects on leaf gas exchange, vegetative growth and yield of black pepper plants using Gliricidia sepium as living support

“…Thus, from the results of the present research, it is inferred that, at least in part, the cultivation with a live tutor of G. sepium associated with the supply of adequate amounts of N can benefit the black pepper in periods of the year of lower water regime. Oliveira et al (2018), when evaluating physiological responses to photosynthesis in black pepper plants in intercropping with rubber trees, observed that in summer, there was lower temperature and higher A value in treatments with rubber trees 2 and 5 meters away from the pepper tree, when compared to A values in plants in full sun, suggesting that during the warmer periods of the year shade can improve the photosynthetic functioning of black pepper, as previously reported for other species (Dai et al,, 2009;Zhu et al, 2012). It is well known that shading causes microclimatic changes in many agricultural crops, especially in plants located in rows closest to trees, resulting in physiological and growth changes (Partelli et al, 2014;Araújo et al, 2016;, which agrees with the findings of the present study since the SL, due to its crown, promotes certain shading of the black pepper tree.…”

“…Measurements were performed between 9 and 11 h, under ambient CO 2 concentration (c.a. 398 µmol CO 2 mol −1 ) and under saturating photosynthetically active radiation of 1,000 µmol m -2 s -1 (Oliveira et al, 2018;Silvestre et al, 2017). The instantaneous water use efficiency (WUE) was estimated as the quotient between A and E (Hatfield et al, 2011).…”