Enhancing productivity and sustainability of ravine lands through horti-silviculture and soil moisture conservation: A pathway to land degradation neutrality.

Ravine lands are the worst type of land degradation affecting soil quality and biodiversity. Crop production in such lands is impossible without adopting proper conservation measures. In-situ moisture conservation techniques could play an instrumental role in restoring ravine lands by improving soil moisture. We hypothesized that restoring ravine land through a combination of tree planting, fruit crop cultivation, and in-situ moisture conservation practice would result in significant improvements in productivity, profitability, and soil fertility. An experiment was conducted involving the combination of Malabar Neem (Melia dubia) and Dragon fruit (Hylocereus undatus) in conjunction with in-situ soil moisture conservation measures specifically involving half-moon structures (HM). The experiment was conducted under randomized block design (RBD) comprising eight treatments. These treatments include sole Melia cultivation (MD 3m × 3m), sole cultivation of dragon fruit (DF 3m × 3m), silviculture system (MDF-3m × 3m), horti-silviculture system with larger spacing (MDF-4m × 4m), sole Melia cultivation with in-situ moisture conservation (MDH-3m × 3m), sole Dragon fruit cultivation with in-situ moisture conservation (DFH-3m × 3m), horti-silviculture system of Melia and Dragon fruit with in-situ moisture conservation (MDFH-3m × 3m), and horti-silviculture system with larger spacing and in-situ moisture conservation (MDFH-4m × 4m). Each treatment was replicated thrice to evaluate their impact on productivity, profitability, soil fertility, and carbon sequestration for 8 years (2016-2023). The results revealed that the horti-silviculture system (MDFH-3 × 3 m) exhibited the highest total tree biomass and total carbon sequestration with an increase of 183.2% and 82.8% respectively, compared to sole Melia cultivation without HM and sole Melia with HM. Furthermore, sole Melia with HM augmented soil nutrients (N, P, K, and SOC) by 74.4%, 66.4%, 35.2%, and 78.3%, respectively, compared to control (no planting), with performance at par with MDFH-3 × 3 m. Similarly, sole Melia with HM enhanced SOC stock and SOC sequestration rate by 79.2% and 248% over control. However, it was found at par with MDFH-3 × 3 m. The horti-silviculture system (MDFH-3 × 3 m) consistently produced the highest fruit yield throughout the years surpassing other treatments. This treatment increased the average dragon fruit yield by 115.3% compared to sole dragon fruit without HM. Hence, the adoption of the horti-silviculture system (MDFH-3 × 3 m) could be a promising strategy for achieving enhanced environmental and economic benefits in ravine lands. Therefore, dragon fruit based horti-silviculture system (MDFH-3 × 3 m) could be recommended for restoration of ravine lands, improving land productivity, and mitigating impact of soil erosion particularly in Western India or similar agro-climatic regions of the world.

Agroforestry for controlling soil erosion and enhancing system productivity in ravine lands of Western India under climate change scenario.

Soil erosion in semi-arid climate leading to the development of ravine lands is the most severe form of land degradation. Ravine lands are formed when soil is not fully covered by the vegetation throughout the year and sporadic vegetation is not able to bind the soil particles from being washed away by rainfall. Throughout the globe, ravine lands have severe limitations for their rehabilitation and sustainable utilization as a consequence of its unique topographical features. Climatic and edaphic stresses make crop production extremely challenging in these lands. Practicing sole cropping promotes erosion, produces low crop yield, utilizes high energy, and emits greenhouse gasses (GHGs). Tree cultivation either sole or in combination with crops (agroforestry) has a strong potential to control erosion, produce sustainable economic yield, reduce energy consumption, and sequester greater amount of atmospheric carbon dioxide in biomass and soil carbon pools besides providing various ecosystem services. Therefore, practicing agroforestry could be a promising approach to obtain the greater environmental and economic benefits in the ravine lands. The present study was conducted on three systems, i.e., sole crop cultivation (cowpea + castor), agroforestry (sapota + cowpea + castor), and sole sapota plantation, to evaluate their impact on soil erosion, runoff, system productivity, profitability, energetics, and carbon sequestration during the 4-year period (2017-2020). The results revealed that agroforestry reduced the total soil loss and runoff by 37.7% and 19.1%, respectively, compared to the sole crop cultivation. Likewise, the highest system productivity as cowpea equivalent yield (CEY) was obtained under agroforestry system that increased the CEY by 162% and 81.9%, compared to sole crop and sole tree plantation, respectively. The climate change mitigation potential in terms of net carbon balance was observed highest in sole tree plantation (8.4 t/ha) followed by agroforestry system (5.9 t/ha) and lowest in sole cropping system (-2.8 t/ha). Therefore, an agroforestry system could be recommended for controlling soil erosion, improving system productivity and profitability, and reducing energy consumption as well as mitigating climate change in ravine lands.

Fertilization in vitro of mouse ova from inbred and outbred strains: complete preimplantation embryo development in glucose-supplemented KSOM.

A new medium derived from the use of sequential simplex optimization methods (SOM) that overcomes the block to development beyond two cells in vitro in embryos of the CF1-cultured strain of mouse has recently been described. Contrary to previous reports, glucose was shown to have no significant inhibiting effect on embryo development to the blastocyst stage in SOM. A modification of SOM, designated KSOM, with an increased concentration of Na+ (95 mM) and K+ (2.5 mM), which has been described elsewhere, also supports growth beyond the two-cell block. KSOM produces a higher rate of compaction, a larger yield of blastocysts, and an increased rate of cell division of the trophoblast cells. We have reexamined the glucose effect by varying the concentration of glucose (either 0.2 mM or 5.56 mM) in KSOM and determined the ability of these media to support preimplantation development of CF1 female x B6D2F1 male zygotes through the blastocyst stage. Glucose is shown to have no significant inhibiting effect on development to the blastocyst stage. The yield of blastocysts is typically 85%-90%. A modification of KSOM derived from this study, designated modified KSOM, with an increased concentration of glucose (5.56 mM) and supplemented with 4 mg ml-1 BSA is now shown to support high rates of fertilization in vitro of CF1 ova with hybrid B6D2F1/CrlBR sperm and subsequent development of zygotes beyond the two-cell stage to blastocysts in high yield.(ABSTRACT TRUNCATED AT 250 WORDS)