Combined application of biochar and peatmoss for mitigation of drought stress in tobacco.

Drought poses a significant ecological threat that limits the production of crops worldwide. The objective of this study to examine the impact of soil applied biochar (BC) and peatmoss (PM) on the morpho-biochemical and quality traits of tobacco plants under drought conditions. In the present experiment work, a pot trial was conducted with two levels of drought severity (~ well-watered 75 ± 5% field capacity) and severe drought stress (~ 35 ± 5% field capacity), two levels of peatmoss (PM) @ 5% [PM+ (with peatmoss) and PM- (without peatmoss)] and three levels of rice straw biochar (BC0 = no biochar; BC1 = 150 mg kg- 1; and BC2 = 300 mg kg- 1 of soil) in tobacco plants. The results indicate that drought conditions significantly impacted the performance of tobacco plants. However, the combined approach of BC and PM significantly improved the growth, biomass, and total chlorophyll content (27.94%) and carotenoids (32.00%) of tobacco. This study further revealed that the drought conditions decreased the production of lipid peroxidation and proline accumulation. But the synergistic approach of BC and PM application increased soluble sugars (17.63 and 12.20%), soluble protein (31.16 and 15.88%), decreased the proline accumulation (13.92 and 9.03%), and MDA content (16.40 and 8.62%) under control and drought stressed conditions, respectively. Furthermore, the combined approach of BC and PM also improved the leaf potassium content (19.02%) by limiting the chloride ions (33.33%) under drought stressed conditions. Altogether, the balanced application of PM and BC has significant potential as an effective approach and sustainable method to increase the tolerance of tobacco plants subjected to drought conditions. This research uniquely highlights the combined potential of PM and BC as an eco-friendly strategy to enhance plant resilience under drought conditions, offering new insights into sustainable agricultural practices.

Optimal Resource Allocation Policies for Multi-User Backscatter Communication Systems.

This paper considers a backscatter communication (BackCom) system including a reader and N tags, where each tag receives excitation signals transmitted by the reader and concurrently backscatters information to the reader in time-division-multiple-access (TDMA) mode. In this system, we aim to maximize the total system goodput by jointly optimizing reader transmission power, time allocation, and reflection ratio for the cases of passive and semi-passive tags. For each case, an optimization problem is formulated, which is non-convex and can be solved by being decomposed into at most N feasible sub-problems based on the priority of allocated reader transmission power. First, for the passive tags case, by solving the convex sub-problems sequentially and comparing their maximum total goodput, we derive the optimal resource allocation policy. Then, for the semi-passive tags case, we find a close-to-optimal solution, since each sub-problem can be reformulated as a biconvex problem, which is solved by a proposed block coordinate descent (BCD)-based optimization algorithm. Finally, simulation results demonstrate the superiority of the proposed resource allocation policies.

Impact of dormancy periods on some physiological and biochemical indices of potato tubers.

Background: Storage of potato tubers is an essential stage of the supply chain, from farm to consumer, to efficiently match supply and demand. However, the quality and yield of potatoes are influenced by physiological changes during storage. Methods: This study tested the physiological and biochemical indices in three potato varieties (YunSu 108, YunSu 304 and YunSu 306) during their dormancy periods. Results: Three potato varieties with different dormancy periods were used to follow changes in starch, protein and several enzymes during storage. The starch and sugar content of the long-dormant variety (YunSu 108, LDV) were stable, whereas those of the short-dormant variety (YunSu 306, SDV) were variable. Starch synthase activity in the three varieties was initially high, then decreased; the starch content of LDV was relatively stable, that of the medium-dormant variety (YunSu 304, MDV) increased with storage time and peaked at sprouting, and that of SDV was low but variable. The sucrose synthase activity of LDV was significantly higher (p < 0.05) than MDV and SDV in the middle storage period. Two spikes were observed in the invertase activity of SDV, whereas those of MDV and LDV were stable. The reducing sugar content of LDV increased significantly before sprouting, that of MDV slowly decreased and that of SDV dropped sharply. During the whole storage period, pectinase activity in LDV did not change significantly, whereas pectinase in MDV and SDV decreased. The cellulase and protein contents initially increased and then decreased in LDV, and steadily decreased in MDV and SDV. Conclusion: The metabolic indices related to starch and sugar in the LDV were relatively stable during storage, whereas those of the SDV varied greatly. SDV showed increased sucrose, reducing sugars and cellulose; LDV PCA plots clustered in the positive quadrant of PC1 and the negative quadrant of PC2, with increased protein, sucrose synthase and starch; MDV had increased soluble starch synthase.