Assessment of a novel soil nutrient imaging technique, forage productivity and the soil health status of silage corn and forage soybean cultivated as mono or intercrop under cool climatic conditions

Zaeem, Muhammad (2018) Assessment of a novel soil nutrient imaging technique, forage productivity and the soil health status of silage corn and forage soybean cultivated as mono or intercrop under cool climatic conditions. Masters thesis, Memorial University of Newfoundland.

[English] PDF - Accepted Version Available under License - The author retains copyright ownership and moral rights in this thesis. Neither the thesis nor substantial extracts from it may be printed or otherwise reproduced without the author's permission. Download (5MB)

Abstract

Inadequate supply and inferior forage quality are major challenges facing Newfoundland and Labrador dairy industry. Therefore, dairy farmers have to depend on substantial forage imports from mainland. To overcome forage shortage, there is an increasing trend to add silage corn as a high biomass producing crop in existing forage production systems in the Province by using different nutrient management practices including the application of nutrient laden dairy manure (DM) or inorganic fertilizers (IF) for sustainable forage production. Therefore, I investigated the effects of silage corn and forage soybean cultivated as monocropping (MC) or intercropping (IC) on total forage production, forage nutritional quality, and soil health status. I further evaluated the effects of different DM and IF applications on the spatial distribution and quantification of essential nutrients in the root rhizospheres by employing a novel approach consisting of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Three forage soybean varieties (Big Fellow RR, Game Keeper RR, Kester’s Bob White Trailing Soybean) were IC with two silage corn genotypes (Yukon-R and DKC26‒28RIB) using a random complete block design (RCBD). Study results revealed that corn-soybean IC enhanced the agronomic performance, forage production and nutritional quality compared to MC. The land equivalent ratio surpassed 1, expressing IC had advantages over MC. IC reduced the RS-pH with a concomitant increase in RS-APase activity, that was affiliated with an increase in RS-Pavailable compared to corn and soybean MC. The soil active microbial community composition was also improved in IC systems compared to MC. Superior quality forage nutritional quality was observed in the IC treatment and included higher crude proteins, essential minerals, omega-3 and omega-6 fatty acids and reduced fiber contents compared to MC. Furthermore, LA-ICP-MS imaging revealed major variation in the spatial distribution of essential minerals in the soil A horizon, and quantitative differences in amounts of nutrients present in the root rhizospheres following different nutrient management practices. Collectively, these finding suggested that silage corn and forage soybean IC could be a viable approach to increase forage production with improved nutritional quality, enhanced the soil chemical or biological activities with better nutrient availability in the plant root zone following cultivation under cool climates in boreal ecosystem characteristic of Newfoundland and Labrador, Canada.

Actions (login required)

View Item