Regulation of Phosphorus and Zinc Uptake in Relation to Arbuscular Mycorrhizal Fungi for Better Maize Growth

Zinc (Zn) is an important micronutrient for plants, whose deficiency in alkaline soils creates hurdles in the achievement of optimum crop growth. Moreover, overuse of phosphorus (P) fertilizers often causes Zn immobilization in the soil. The employment of arbuscular mycorrhizal fungi (AMF) could be potentially environmentally friendly technology in this regard. Therefore, a pot experiment was conducted to assess the beneficial role of AMF (Glomus species) on maize under low and high P and Zn levels. Seven levels of Zn (0, 20, 40, 60, 80, 100 and 120 mg Zn kg−1 soil ZnSO4·7H2O) and three levels of P (0, 14.5, 29 and 58 kg ac−1 as single superphosphate) were applied with (M+) and without AMF (M−). The results showed that a high application rate of Zn (100 and 120 mg Zn kg−1 soil) restricted P translocation in plants and vice versa. Moreover, the nutritional status of mycorrhizal plants (AM) was better than non-mycorrhizal (NM) plants. AM plants showed a maximum positive response at 20 mg Zn kg−1 soil, or 29 kg P ac−1. In response to 20 mg Zn kg−1 soil, root colonization was maximum, which enhanced the maize nutrient concentration in shoots. In conclusion, AMF inoculation (M+) with P (29 kg ac−1) and Zn (20 mg kg−1) is efficacious for improving maize’s growth and nutrition. More investigations are suggested at the field level under different agroclimatic zones to ascertain whether P (29 kg ac−1) or Zn (20 mg kg−1) with AMF is the best treatment for maize growth optimization.

Arbuscular Mycorrhizal Fungi Association with Some Selected Medicinal Plants

Arbuscular mycorrhizal fungi (AMF) are group of fungi of the order Glomales that form symbiotic association with plant roots and enhance the uptake of nutrients, and improve plant growth and yield. This study was conducted to investigate the occurrence of arbuscular mycorrhizal fungi in the rhizospheres of some commonly grown medicinal plants in Maiduguri viz; Aloe vera, Mentha, Cymbopogon citrates and Ocimum gratissimum. The results revealed all the plants have formed mycorrhiza symbiosis. Arbuscular mycorrhizal fungi spores from five genera (Glomus, Acaulospora, Dentiscutata, Scutellispora and Gigaspora were isolated and identified. Cymbopogon citrates significantly recorded the highest total AMF spore counts (90±4.17) while Aloe vera recorded the least (54±2.28). Amongst the five mycorrhiza genus Glomus species were comparatively higher under all plant species, while, Dentiscutata and Gigaspora had the lowest spore counts. Highest percent root colonization (72±4.23%) was recorded under Cymbopogon citrates and Aloe vera recorded the least (55.5 ±2.41%). The study confirmed mycorrhiza association with all the plants, however, AMF spore counts diversity varies with plant species. Arbuscular mycorrhizal fungi could be inoculated to soils with scanty or ineffective spores for enhanced plant nutrition and growth of medicinal plants.

Arbusculer mycorrizal fungal investigation in the weeds of wheat field of Tehsil Tangi, District Charsadda, Khyber Pakhtunkhwa.

An investigation has been make about the Arbuscular Mycorrhizal Fungi (AMF) spore density in weeds plants with soil selected from the Tehsil Tangi. The spore density was observed in all weeds plants in the host growth stage. The maximum Arbuscular Mycorrhizal Fungi (AMF) spore density wasfound in Chenopodium album (93.00±74.02) and Scandix iberica (89.00±92.08) at vegetative stage. The Glomus species are dominant in the rhizosporic soil of weeds plants followed in Aculospora, and Sclerocystis. The lowest Glomus spore density are present in Fumariapureflora (10.67±15.89).The spore density of AMF had a strong positive correlation with soil PH and carbon is negative correlation with P content of the soil. Thehighest Vesicles are investigated in.Euphorbia heliscopia(14.33±9.5) and lowest in Circium arevesis (3.33±1.53) .Arbuscules was higher in Euphorbia heliscopia (18.67±18.72) and lowest in Circium arvensis (2.00±1.73). Highest External hyphae was found in Silene conidia (4.00±1.73) and lowest in Anagallus arrensis. Internal hyphae were in Rananculas maricates (6.33±5.13) and lowest in Melolotus indica(0.67±0.58). While totally absent in Brassica nigra (Brassicaece).

The Effects of Inoculation with Three Glomus Species on Growth and Pb Uptake by Hemp (Cannabis Sativa) in a Pb-Contaminated Soil

Increasing levels of hazardous heavy metals, which enter soil and water ecosystems have had a detrimental effect on global living organisms and needs special attention. The effect of inoculation with three Glomus mycorrhizal fungi (G. mosseae, G. etunicatum and G. constrictum) on hemp growth and some biological properties was evaluated in a soil contaminated with different levels of lead (0, 600, 1200 and 1800mg·kg-1 Pb soil) in the form of Pb(NO3)2. The results show that shoot and root dry weights decreased with increasing Pb levels in soil. But Pb concentration in roots and shoots of hemp increased significantly with increasing Pb levels in soil. However the growth of mycorrhizal inoculated hemps was significantly higher than that of non-inoculated hemp. Mycorrhizal inoculation increased the concentration of Pb in the shoot and root of hemp. In this study, both translocation factor (TF) and enrichment factor (EF) were < 1 and decreased with increasing Pb concentration in soil. The TF was higher in non-inoculated hemp than inoculated hemps. It shows the inhibition effect of mycorrhiza in translocation of Pb from root to shoot. The EF of all inoculated hemps (0.18) was significantly greater than non-inoculated hemp (0.17), showing increased uptake of Pb due to inoculation with mycorrhiza. Simple linear regressions show that the diethylenetriaminepentaacetic acid (DTPA) extractable Pb is more suitable index for evaluating the toxicity effect of soil Pb than the total Pb content.

The Indigenous endomycorrhizal fungi at salak (Salacca zalacca) plantations in Bali, Indonesia and their colonization of the roots

Rai IN, Suada IK, Proborini M, Wiraatmaja IW, Semenov M, Krasnov G. 2019. Indigenous endomycorrhizal fungi at salak (Salacca zalacca) plantations in Bali, Indonesia and their colonization of the roots. Biodiversitas 20: 2410-2416. Cultivation of snake fruit, commonly known as salak usually done organically on dry land with limited fertilizer in Bali. This research aimed to observe and to identify the indigenous endomycorrhizal fungi on salak roots. The exploration was carried out by collecting soil and root samples in salak producing areas in Bali, i.e. Bebandem and Selat of Karangasem Regency, Payangan of Gianyar, and Pupuan of Tabanan Regency. At each location, 9 random samples were taken, resulting in a total of 36 samples. Spore extraction was carried out using a wet filtration technique followed by centrifugation according to the method by Brunndrett et al. (2009). Morphological identification was carried out at the genus and species level using the Manual for Identification of Mycorrhiza Fungi for identifying Vesicular-Arbuscular-Mycorrhiza (VAM) fungi (Schenk and Perez, 1990), while molecular identification was carried out according to Tedersoo et al. (2014). The percentage of root infections was carried out using the coloring method with trypan blue. The results showed there were only two genera of endomycorrhizae (Glomus and Entrophospora) identified at the locations of study sites. The results also showed that samples from Bebandem and Selat regions had 3 Glomus species, Payangan had 3 Glomus species and 1 Entrophospora species, while in Pupuan had only 2 Glomus species. Identification results based on morphological characters showed that all species in the genus Glomus consisted of 3 species, namely Glomus sp-1, Glomus sp-2, and Glomus sp-3, while one species in the genus Entrophospora was Entrophospora sp. Genetic identification results based on the nucleotide arrangement showed that Glomus sp-1 concluded as Glomus cubence, Glomus sp-2 concluded as Glomus custos, and Glomus sp-3 concluded as Glomus indicum, while Entrophospora species concluded as Entrophospora_sp_SH197095.06FU. The average of root colonization/ infection was very high, reaching 93.33% in Bebandem and Selat, 95.00% in Pupuan, and 100% in Payangan. The very high root infection rates indicated that the indigenous endomycorrhiza found in these areas was very adaptive in salak plantation, so there is an opportunity to be developed as biofertilizers.

COMPARING THE ASSOCIATION OF ARBUSCULAR MYCORRHIZAL FUNGI WITH WHEAT CROP FROM DISTRICT MARDAN AND CHARSADDA

Arbuscular mycorrhizal fungi (AMF) are one of the important microbes of the soil microflora which can interact with other soil microbes or plant roots. AM fungi have been known to improve nutrients uptake of plants from deep soil regions where plant roots cannot normally reach and results in improved plant growth. The present study was conducted to investigate the presence of AM fungi during various growth stages of Wheat (Triticum aestivum, L.) crops grown in different locations of District Mardan and District Charsadda, KP, Pakistan and to determine the relationship between AM fungi and physiochemical characteristic of soil. A total of fifteen wheat fields were studied at host growth stages (vegetative stage and fruiting stage). All the wheat fields were found to have AMF association ranged from 24-100%, 27-171gm-200 spores density. The results showed that the highest AMF root colonization and spores density has been found at fruiting stage as compared to vegetative stage. This study reports three species of AM fungi i.e. Glomus spp., Sclerocystis spp. and Acaulospora spp. from the studied sites on the basis of spore identification. This study also reports that in vegetative stage of wheat, the Glomus species was in abundance and in fruiting stage, Sclerocystis species was abundant. Glomus species was observed to be dominant at all stages and locations.