Abstract
Zinc (Zn) is an indispensable element for proper plant growth. A sizeable proportion of the inorganic Zn that is added to soil undergoes a transformation into an insoluble form. Zinc-solubilizing bacteria (ZSB) have the potential to transform the insoluble Zn into plant-accessible forms and are thus promising alternatives for Zn supplementation. The current research was aimed at investigating the Zn solubilization potential of indigenous bacterial strains and to evaluate their impact on wheat growth and Zn biofortification. A number of experiments were conducted at the National Agriculture Research Center (NARC), Islamabad, during 2020-21. A total of 69 strains were assessed for their Zn-solubilizing ability against two insoluble Zn sources (ZnO and ZnCO 3 ) using plate assay techniques. During the qualitative assay, the solubilization index and solubilization efficiency were measured. The qualitatively selected Zn-solubilizing bacterial strains were further tested quantitatively using broth culture for Zn and phosphorus (P) solubility. Tricalcium phosphate was used as insoluble source of P. The results showed that broth culture pH was negatively correlated with Zn solubilization, i.e., ZnO (r 2 = 0.88) and ZnCO 3 (r 2 = 0.96). Ten novel promising strains, i.e., Pantoea sp. NCCP-525, Klebsiella sp. NCCP-607, Brevibacterium sp. NCCP-622, Klebsiella sp. NCCP-623, Acinetobacter sp. NCCP-644, Alcaligenes sp. NCCP-650, Citrobacter sp. NCCP-668, Exiguobacterium sp. NCCP-673, Raoultella sp. NCCP-675, and Acinetobacter sp. NCCP-680, were selected from the ecology of Pakistan for further experimentation on wheat crop based on plant growth-promoting rhizobacteria (PGPR) traits, i.e., solubilization of Zn and P in addition to being positive for nif H and acd S genes. Before evaluating the bacterial strains for plant growth potential, a control experiment was also conducted to determine the highest critical Zn level from ZnO to wheat growth using different Zn levels (0.1, 0.05, 0.01, 0.005, and 0.001% Zn) against two wheat varieties (Wadaan-17 and Zincol-16) in sand culture under glasshouse conditions. Zinc-free Hoagland nutrients solution was used to irrigate the wheat plants. As a result, 50 mg kg -1 of Zn from ZnO was identified as the highest critical level for wheat growth. Using the critical level (50 mg kg -1 of Zn), the selected ZSB strains were inoculated alone and in consortium to the seed of wheat, with and without the use of ZnO, in sterilized sand culture. The ZSB inoculation in consortium without ZnO resulted in improved shoot length (14%), shoot fresh weight (34%), and shoot dry weight (37%); with ZnO root length (116%), it saw root fresh weight (435%), root dry weight (435%), and Zn content in the shoot (1177%) as compared to the control. Wadaan-17 performed better on growth attributes, while Zincol-16 had 5% more shoot Zn concentration. The present study concluded that the selected bacterial strains show the potential to act as ZSB and are highly efficient bio-inoculants to combat Zn deficiency, and the inoculation of these strains in consortium performed better in terms of growth and Zn solubility for wheat as compared to individual inoculation. The study further concluded that 50 mg kg -1 Zn from ZnO had no negative impact on wheat growth; however, higher concentrations hampered wheat growth.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 17
Claim · model-written summary
Broth pH correlated negatively with ZnO solubilization.
- Taxon
- wheat
Triticum aestivumt0 - Outcome
- Zn solubilizatione0
- Direction
- negativelye0
- Value
- r 2 = 0.88e0
- Qualifier
- ZnOe0
- Setting
- broth culturee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The results showed that broth culture pH was negatively correlated with Zn solubilization, i.e., ZnO (r 2 = 0.88) and ZnCO 3 (r 2 = 0.96).”
t0“wheat”
Claim · model-written summary
Broth pH correlated negatively with ZnCO 3 solubilization.
- Taxon
- wheatTriticum aestivumt0
- Outcome
- Zn solubilizatione0
- Direction
- negativelye0
- Value
- r 2 = 0.96e0
- Qualifier
- ZnCO 3e0
- Setting
- broth culturee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The results showed that broth culture pH was negatively correlated with Zn solubilization, i.e., ZnO (r 2 = 0.88) and ZnCO 3 (r 2 = 0.96).”
t0“wheat”
Claim · model-written summary
Ten bacterial strains were selected for wheat tests using Zn and P solubilization and gene traits.
- Taxon
- wheatTriticum aestivume0
- Outcome
- Ten novel promising strainse0
- Value
- Tene0
- Qualifier
- solubilization of Zn and Pe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Ten novel promising strains, i.e., Pantoea sp. NCCP-525, Klebsiella sp. NCCP-607, Brevibacterium sp. NCCP-622, Klebsiella sp. NCCP-623, Acinetobacter sp. NCCP-644, Alcaligenes sp. NCCP-650, Citrobacter sp. NCCP-668, Exiguobacterium sp. NCCP-673, Raoultella sp. NCCP-675, and Acinetobacter sp. NCCP-680, were selected from the ecology of Pakistan for further experimentation on wheat crop based on plant growth-promoting rhizobacteria (PGPR) traits, i.e., solubilization of Zn and P in addition to being positive for nif H and acd S genes.”
Claim · model-written summary
The highest critical ZnO zinc level for wheat growth was 50 mg kg -1.
- Taxon
- wheatTriticum aestivume0
- Treatment
- Zn from ZnOe0
- Outcome
- wheat growthe0
- Direction
- higheste0
- Value
- 50 mg kg -1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“As a result, 50 mg kg -1 of Zn from ZnO was identified as the highest critical level for wheat growth.”
Claim · model-written summary
Consortium inoculation without ZnO increased shoot length by 14%.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- ZSB inoculation in consortiume0
- Interactor
- ZSBe0symbiont
- Outcome
- shoot lengthe0
- Direction
- improvede0
- Value
- 14%e0
- Qualifier
- without ZnOe0
- Comparator
- the controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ZSB inoculation in consortium without ZnO resulted in improved shoot length (14%), shoot fresh weight (34%), and shoot dry weight (37%); with ZnO root length (116%), it saw root fresh weight (435%), root dry weight (435%), and Zn content in the shoot (1177%) as compared to the control.”
t0“wheat”
Claim · model-written summary
Consortium inoculation without ZnO increased shoot fresh weight by 34%.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- ZSB inoculation in consortiume0
- Interactor
- ZSBe0symbiont
- Outcome
- shoot fresh weighte0
- Direction
- improvede0
- Value
- 34%e0
- Qualifier
- without ZnOe0
- Comparator
- the controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ZSB inoculation in consortium without ZnO resulted in improved shoot length (14%), shoot fresh weight (34%), and shoot dry weight (37%); with ZnO root length (116%), it saw root fresh weight (435%), root dry weight (435%), and Zn content in the shoot (1177%) as compared to the control.”
t0“wheat”
Claim · model-written summary
Consortium inoculation without ZnO increased shoot dry weight by 37%.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- ZSB inoculation in consortiume0
- Interactor
- ZSBe0symbiont
- Outcome
- shoot dry weighte0
- Direction
- improvede0
- Value
- 37%e0
- Qualifier
- without ZnOe0
- Comparator
- the controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ZSB inoculation in consortium without ZnO resulted in improved shoot length (14%), shoot fresh weight (34%), and shoot dry weight (37%); with ZnO root length (116%), it saw root fresh weight (435%), root dry weight (435%), and Zn content in the shoot (1177%) as compared to the control.”
t0“wheat”
Claim · model-written summary
Consortium inoculation with ZnO increased root length by 116%.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- ZSB inoculation in consortiume0
- Interactor
- ZSBe0symbiont
- Outcome
- root lengthe0
- Direction
- improvede0
- Value
- 116%e0
- Qualifier
- with ZnOe0
- Comparator
- the controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ZSB inoculation in consortium without ZnO resulted in improved shoot length (14%), shoot fresh weight (34%), and shoot dry weight (37%); with ZnO root length (116%), it saw root fresh weight (435%), root dry weight (435%), and Zn content in the shoot (1177%) as compared to the control.”
t0“wheat”
Claim · model-written summary
Consortium inoculation with ZnO increased root fresh weight by 435%.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- ZSB inoculation in consortiume0
- Interactor
- ZSBe0symbiont
- Outcome
- root fresh weighte0
- Direction
- improvede0
- Value
- 435%e0
- Qualifier
- with ZnOe0
- Comparator
- the controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ZSB inoculation in consortium without ZnO resulted in improved shoot length (14%), shoot fresh weight (34%), and shoot dry weight (37%); with ZnO root length (116%), it saw root fresh weight (435%), root dry weight (435%), and Zn content in the shoot (1177%) as compared to the control.”
t0“wheat”
Claim · model-written summary
Consortium inoculation with ZnO increased root dry weight by 435%.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- ZSB inoculation in consortiume0
- Interactor
- ZSBe0symbiont
- Outcome
- root dry weighte0
- Direction
- improvede0
- Value
- 435%e0
- Qualifier
- with ZnOe0
- Comparator
- the controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ZSB inoculation in consortium without ZnO resulted in improved shoot length (14%), shoot fresh weight (34%), and shoot dry weight (37%); with ZnO root length (116%), it saw root fresh weight (435%), root dry weight (435%), and Zn content in the shoot (1177%) as compared to the control.”
t0“wheat”
Claim · model-written summary
Consortium inoculation with ZnO increased Zn content in the shoot by 1177%.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- ZSB inoculation in consortiume0
- Interactor
- ZSBe0symbiont
- Outcome
- Zn content in the shoote0
- Direction
- improvede0
- Value
- 1177%e0
- Qualifier
- with ZnOe0
- Comparator
- the controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ZSB inoculation in consortium without ZnO resulted in improved shoot length (14%), shoot fresh weight (34%), and shoot dry weight (37%); with ZnO root length (116%), it saw root fresh weight (435%), root dry weight (435%), and Zn content in the shoot (1177%) as compared to the control.”
t0“wheat”
Claim · model-written summary
Wadaan-17 performed better on growth attributes.
- Taxon
- wheatTriticum aestivumt0
- Material
- Wadaan-17e0
- Outcome
- growth attributese0
- Direction
- bettere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Wadaan-17 performed better on growth attributes, while Zincol-16 had 5% more shoot Zn concentration.”
t0“wheat”
Claim · model-written summary
Zincol-16 had 5% more shoot Zn concentration.
- Taxon
- wheatTriticum aestivumt0
- Material
- Zincol-16e0
- Outcome
- shoot Zn concentratione0
- Direction
- moree0
- Value
- 5%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Wadaan-17 performed better on growth attributes, while Zincol-16 had 5% more shoot Zn concentration.”
t0“wheat”
Claim · model-written summary
The selected strains were judged promising zinc bioinoculants.
- Taxon
- wheatTriticum aestivumt0
- Outcome
- highly efficient bio-inoculants to combat Zn deficiencye0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The present study concluded that the selected bacterial strains show the potential to act as ZSB and are highly efficient bio-inoculants to combat Zn deficiency, and the inoculation of these strains in consortium performed better in terms of growth and Zn solubility for wheat as compared to individual inoculation.”
t0“wheat”
Claim · model-written summary
Consortium inoculation outperformed individual inoculation on wheat growth and Zn solubility.
- Taxon
- wheatTriticum aestivume0
- Treatment
- inoculation of these strains in consortiume0
- Outcome
- growth and Zn solubility for wheate0
- Direction
- bettere0
- Comparator
- individual inoculatione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The present study concluded that the selected bacterial strains show the potential to act as ZSB and are highly efficient bio-inoculants to combat Zn deficiency, and the inoculation of these strains in consortium performed better in terms of growth and Zn solubility for wheat as compared to individual inoculation.”
Claim · model-written summary
ZnO zinc at 50 mg kg -1 had no negative effect on wheat growth.
- Taxon
- wheatTriticum aestivume0
- Treatment
- 50 mg kg -1 Zn from ZnOe0
- Outcome
- wheat growthe0
- Direction
- no negative impacte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The study further concluded that 50 mg kg -1 Zn from ZnO had no negative impact on wheat growth; however, higher concentrations hampered wheat growth.”
Claim · model-written summary
Higher Zn concentrations hampered wheat growth.
- Taxon
- wheatTriticum aestivume0
- Treatment
- higher concentrationse0
- Outcome
- wheat growthe0
- Direction
- hamperede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The study further concluded that 50 mg kg -1 Zn from ZnO had no negative impact on wheat growth; however, higher concentrations hampered wheat growth.”
The same questions in other papers
zinc oxide · growth · Triticum aestivum (wheat)Results differ
2 papers in the same direction as this paper · 25 in the opposite direction
- positive
- positive
- positive
24 papers more in this group
See all 28 papers →zinc atom · growth · Triticum aestivum (wheat)Results differ
44 papers in the same direction as this paper · 155 in the opposite direction
- positive
- negative
- positive
196 papers more in this group
See all 200 papers →inoculation · nutrient: content · Triticum aestivum (wheat)Positive and negative results
262 papers in the same direction as this paper · 13 in the opposite direction · 1 reporting no difference from an alternative
- positive
- positive
- positive
273 papers more in this group
See all 277 papers →inoculation · growth · Triticum aestivum (wheat)Positive and negative results
475 papers in the same direction as this paper · 55 in the opposite direction · 1 reporting no difference from an alternative
- positive
- positive
- no effect
528 papers more in this group
See all 532 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.