[Objective] The objective of the study is to explore the effect of monosodium glutamate wastewater manure(hereinafter referred to as manure) mixed with inorganic fertilizer on the root absorption characteristics and humus composition of rhizosphere soil of watermelon(Citrullus lanatus).[Methods] The present study was conducted to determine the effects of different treatments

i.e. CK(control

no fertilization); N100(pure urea

hereinafter referred to as inorganic fertilizer); M10N90(the proportion of manure and inorganic fertilizer is 10% and 90%); M30N70(the proportion of manure and inorganic fertilizer is 30% and 70%) and M50N50(the proportion of manure and inorganic fertilizer is 50% and 50%) on root activity

construction levels of root system

root morphological characteristics and root exudates

as well as humus composition in the rhizosphere soil of watermelon.[Results] The results indicated that in comparison to N100 treatment

M30N70 treatment significantly increased root activity

and promoted the root growth of watermelon. At the same time

M30N70 treatment also increased the total root length

root surface area

specific root surface area

root volume and root tip number

while the root average diameter obviously decreased. The total root length in the M30N70 treatment increased by 74.63%

40.84%

28.41% and 19.37%

and the specific root surface area was increased by 39.42%

30.82% and 20.89% compared to the treatments of CK

N100

M10N90 and M50N50

respectively. In addition

M30N70 treatment obviously increased the contents of root exudates and humic acid

and increased the ratio of humic acid to fulvic acid

showing 137.36%

47.95% and 33.33% increase in humic acid content compared with the treatments of CK

N100 and M10N90

respectively. However

in M10N90 and M50N50 treatments

less effects was observed than that in M30N70 treatment.[Conclusion] Monosodium glutamate wastewater mixed with inorganic fertilizer

especially M30N70 treatment

is beneficial to the root absorption characteristics and humus composition in the rhizosphere soil of watermelon

and it is recommended as the suitable fertilization proportion in the practice.