A recent study focusing on sugar beets has unveiled significant consequences arising from continuous cropping practices, with promising insights on how bio-organic fertilizer can counteract these effects. Conducted during the 2020-2021 crop season at the Agriculture and Forestry Sciences of Ulanqab, Inner Mongolia, the research aims to evaluate the detrimental impacts of continuous planting on sugar beet's physiological functions, particularly photosynthesis and dry matter distribution.
Sugar beet (Beta vulgaris), regarded as one of the key sugar crop species globally, holds great economic value, particularly within China's Inner Mongolia region, known for its substantial production. The necessity for sustainable agriculture practices emphasizes the significance of this research, especially as current practices often promote continuous cropping due to economic constraints. The results of this study indicate alarming declines of 10.09% to 48.21% across various metrics—including intercellular CO2 concentration (Ci), transpiration rate (Tr), stomatal conductance (Gs), net photosynthetic rate (Pn), and SPAD value—over successive cropping years.
The research employed a split plot system, distinguishing between control (CK) conditions and four treatments with continuous cropping for one to four years (labeled C1 through C4). Results demonstrate how photosynthesis and the accumulation of dry matter critically suffer as continuous cropping intensifies. Overextended exposure to these conditions leads to significant declines not only in photosynthesis metrics but also impacts the dry matters of leaves, petioles, and roots, with reductions reaching 49.79% for whole plants.
Importantly, continuous cropping also results in shifting dry matter distribution away from roots—essential for yield—towards aboveground parts of the plant. This change constrains root productivity and highlights the need for effective agricultural practices to sustain productivity under challenging conditions.
Notably, the application of bio-organic fertilizer at 6000 kg ha−1 was shown to positively impact the photosynthetic performance of sugar beets, particularly within the first two years of continuous cropping. Measurements indicated increases of 12.79% to 22.50% for Pn, 14.76% to 16.47% for Ci, and similar enhancements across other measured parameters. This suggests bio-organic fertilizer's potential role as a corrective measure against the negative physiological repercussions of continuous cropping, potentially benefiting both crop yield and soil health.
While the bio-organic fertilizer demonstrated substantial effects within the initial years of cropping, its impact diminished after the third continuous crop. The findings thereby reinforce the importance of integrating varied farming practices to maintain soil fertility and plant health against the backdrop of continuous cropping challenges faced by sugar beet producers.
Conclusive insights from this study should serve as scientific groundwork for formulating enhanced agricultural frameworks and practices, optimizing production methods for sugar beet cultivation under continuous cropping conditions.
Given the economic and ecological stakes of sugar beet farming, adapting agricultural methodologies to include more sustainable measures, such as bio-organic fertilization, could hold the key to improving yield quality and ensuring agricultural sustainability against the pressures of intensive farming practices.