Influence of Nutrient Management and Crop Rotation on Soil Weed Seedbank in Tharaka Nithi County
Loading...
Date
2024-06
Authors
Mwangi, Obadiah
Wambui, Hottensiah
Mucheru-Muna, Monicah
Journal Title
Journal ISSN
Volume Title
Publisher
JMES
Abstract
Soil weed seedbank in crop fields are largely influenced by crop rotation,
farming practices and nutrient application. For a better understanding of response of
various weed species to these management practices, research was conducted to assess
their effect on the soil weeds seedbank population dynamics in 2017-2019. In this study,
two nutrient level i.e., 225 kg N ha-1
and 125 kg P ha-1
represented high nutrient input
levels applied in commercial systems (Conv-High and Org-High) and 45 kg N ha-1
and 26
kg P ha-1 was used to mimic low nutrient practices common in smallholders farming
systems (Conv-Low and Org-Low) in the region of Tharaka- Nithi County. Trials were
laid out in a randomized complete block design with four treatments replicated four times.
A crop rotation with maize, beans, potatoes and cabbage was used with maize/cabbage 1st
year, maize/beans 2nd year and maize/potatoes 3rd year were established within the four
farming systems. Soil was sampled at a depth of 0-20 cm at the end of every cropping
season. The sample were treated with gibberellic acid to break weed seed dormancy and
seed emergency method was used to determine weed seeds in the soil sample. Results were
analyzed using Simpson’s diversity index and GenStat 14th edition. From the result, 14
weed species were identified. Amaranthus hybridus, Bidens pilosa, Tagete minuta and
Galinsoga parviflora increased in their density with increase in fertilizer application while
Schkurihria pinnata and Portulaca oleracea increased with decrease in fertilizer
application. Crop rotation resulted contributed to weed density decrease. Conventional
high encouraged high weed density compared to Org-high, Conv-Low and Org-low while
as Org-Low encourage high weed species diversity λ= 0.1208 compared to λ= 0.115, λ=
0.1080 and λ= 0.0901 in Org-high, Conv-High and Conv- Low, respectively. In weed
management, fertility inputs and cropping system are the major factor influencing weed
composition in farming systems.
Description
Article
Keywords
Weed, density, diversity, crop rotation, organic, conventional
Citation
Mwangi, O., Wambui, H., & Mucheru-Muna, M. (2024). Influence of nutrient management and crop rotation on soil weed seedbank in Tharaka Nithi County. J. Mater. Environ. Sci., 15 (6), 821, 832, 2017-2019.