Trade of commercial potting substrates: A largely overlooked means of the long-distance dispersal of plants

Although long-distance dispersal (LDD) events are considered to be rare and highly stochastic, they are disproportionately important and drive several large-scale ecological processes. The realisation of the disproportionate importance of LDD has led to an upsurge in studies of this phenomenon; yet, we still have a very limited understanding of its frequency, extent and consequences. Humanity intentionally spreads a high number of species, but a less obvious issue is that it is associated with the accidental dispersal of other plant species. Although the global trade of potted plants and horticultural substrates is capable of dispersing large quantities of propagules, this issue has hardly been studied from an ecological point of view. We used the seedling emergence method to assess the viable seed content of different types of commercial potting substrates to answer the following questions: (i) In what richness and density do substrates contain viable seeds? (ii) Does the composition of substrates influence their viable seed content? and (iii) Are there common characteristics of the species dispersed this way? We detected altogether 438 seedlings of 66 taxa and found that 1 litre of potting substrate contains an average of 13.27 seeds of 6.24 species, so an average 20-litre bag of substrate contains 265 viable seeds. There was a high variability in the seed content of the substrates, as substrates containing cattle manure contained a substantially higher number of species and seeds than substrates without manure. Based on this, this pathway of LDD is an interplay between endozoochory by grazing livestock and accidental human-vectored dispersal, implying that the diet preference of grazing animals largely determines the ability of a plant species to be dispersed this way. According to our results, potting substrates can disperse large quantities of seeds of a wide range of plant species, moreover, these dispersal events occur on very long distances in almost all cases. We conclude that this kind of human-vectored LDD may have complex effects on plant populations and communities; however, as this dispersal pathway is largely understudied and has hardly been considered as a type of LDD, its consequences are still largely unknown and further studies of the issue are of great importance.

Morphometric characteristics and seed germination of Dalbergia granadillo Pittier

Objective: To know the variability and quality of seed in a Dalbergia granadillo Pittier (Fabaceae) population from the Soconusco, Chiapas, Mexico. Design / methodology / approximation: The seed was obtained from six trees during the months of February and March 2020. Two weeks after the seeds were collected, pod and seed variables were determined. Seed length (LS), width (AS), color (CS), weight of 100 seeds (g) (PS) and germination percentage (PG). The results were statistically analysed by analysis of variance using the GLM procedure and the comparison of means by Tukey (P ≤ 0.05) with the SAS 9.0 program. Results: There is wide variation in seed content. The pods registered from 1, 2, 3 and up to four seeds, although pods of one predominated. There are seeds of two colours, dark brown and light brown, and the latter are the most abundant; however, light colored seeds registered higher germination (96%). The weight of 100 seeds registered values ​​of 9.6-9.7 g. Study Limitations / implications: The species has a restricted distribution and presents a low number of individuals in the evaluated populations. Findings / conclusions: The morphometric characteristics of the seeds allowed to identify the variability and quality, mainly in shape, size and coloration of the seeds, as well as the number of seeds per pod.

The Effect of Biofertilization in Fatty Acids Content for Many Flax Varieties

Field experiment was carried out in the fields in Al-Mahaweel district of Babil Governorate during the agricultural season 2020-2021 to estimate the effect of biological fertilization on the content of some fatty acids in flax varieties seeds. A factorial experiment was applied according to a Randomized Complete Block Design (R.C.B.D) with three replications. The experiment included two factors, the first included eight varieties of flax (Indian, Giza11, Giza10, Sahka5, Sahka6, Giza8, Syrian Thorshansity72), The second factor, biological fertilization included four treatments: (control, bacterial fertilization, fungal fertilization and a bacterial-fungal mixture). The fatty acids (a-Linolenic acid, Oleic acid, Linoleic acid, Palmitic acid, Stearic acid) in seeds were determined using HPLC High-Performance Liquid Chromatography. The results showed that Sahka6 Variety was significantly superior on other varieties in seed content of (Oleic acid and Linoleic acid) amounted to (29.70, 28.39) %, respectively, while Indian Variety superiority in seed content of Palmitic acid and Stearic acid amounted to (21.28, 25.27)% respectively. Bacterial fertilizer + Mycorrhiza were significantly superior to the other fertilizer treatments in all indicators of study, and the interaction between a variety and biofertilization did not show any significant differences except for the seed content of (a-Linolenic acid Palmitic acid).

Productivity and viral diseases of seed potatoes depending on the period of potato desiccation

The aim of the research was to determine the crop productivity, yield of tubers of seed fraction and infection of basic potato seeds with viral infection depending on the period of potato desiccation, application of mineral oil Sunspray, the number and species of winged aphids in the Polissia region of Ukraine. The study was conducted in the prebasic seed production nursery garden of the Institute for Potato Research, NAAS under the conditions of spatial isolation from the main sources and vectors of viral infections of potatoes, located in Nemishaieve, Borodiаnka distr., Kyiv region in the southern part of the Polissia region of Ukraine. The subject of the research is pre-basic and basic seed material of potatoes of mid ripening varieties Myroslava, Predslava, Alians. On average for 2018-2020 years of studies, the highest seed yield was obtained by potato desiccation 10 days after flowering of potatoes - 82.4-85.3 %. However, the level of total and seed yields was low. The efficiency of seed potato production increased with the haulm removal after 20 days - with the total yield depending on the variety 20.6-30.0 t/ha, the yield of seed tubers was in the range of 20.6-22.9 t/ha with the seed content in the crop structure - 71.0-76.3 %. Late haulm removal – on 30th and 40th days after potatoes flowering caused an increase in the yield of tubers of non-standard fraction, with desiccation on 30th day, the seed content in the crop decreased by 61.1-66.0 %, and with desiccation on 40th – by 54-59.8 %. Thus, during the early haulm removal, part of the crop was lost, which during haulm removal in the late stages consisted of large tubers. It has been found out, that potato plants, where the haulm removal during 2018, 2019 was carried out within 10 days after flowering, which was 4.0 % (9.0 % for the check) for the Myroslav potato variety, 3.0 % (10.0 % for the check) for the Predslava potato variety and 4.0 % (9.0 % for the check) for the Alians potato variety were the least infected with PVM. The level of PVM infection when removing the haulm on the 10th day after flowering with the application of Sunspray mineral oil at a rate of 6.0 l/ha decreased on average for the three varieties by 1.5–2.5 %. The best option to preserve the quality characteristics of seed potatoes was to desiccate the potato haulm on 20th day after flowering of potato varieties Myroslava, Predslava and Alians and the application of mineral oil Sunspray - 6.0 l / ha. The yield was 28.8-30.0 t/ha, seed fraction 20.6-22.9, seed yield - 71.0-76.3 %, viral PVM infection was 2.0 3.0 %

The Impact of HDPE Plastic Seeds on the Performance of Asphalt Mixtures

Plastic waste processing is a problem that almost several countries in the Asian region are unable to overcome. One of the latest innovations carried out in the field of road pavement construction is mixing HDPE type plastic waste that has been processed into plastic seeds into the asphalt concrete mixture. Previous research has shown that HDPE plastic waste may be reused to improve the physical properties of temperature-sensitive asphalt and improve the stability of asphalt concrete. This study was conducted to determine the effect of using HDPE plastic ore as a mixed additive on the Asphalt Concrete-Wearing Course (AC-WC) using Marshall parameters. Marshall Parameters used are stability, flow, VIM, VMA, VFA, and MQ. The study was conducted in a laboratory by testing 42 samples with different levels of HDPE plastic seeds, mixed using wet methods to determine Marshall Characteristics. Manufacture of test objects using asphalt type, which has a penetration rate of 60/70. The initial research results showed that the optimal asphalt content (OAC) is 5.5%, with the percentage content of HDPE plastic seeds around 0, 1, 2, 3, 4, 5, 6, and 7% compared to asphalt weight. The results showed that the effect of HDPE plastic seed content on the AC-WC mixture increased the value of Marshall Characteristics and met all the requirements of SNI 06-2489-1991. This finding shows that HDPE plastic seeds deserve to be an alternative material for road pavements. Doi: 10.28991/cej-2021-03091744 Full Text: PDF

How Does Mechanical Pearling Affect Quinoa Nutrients and Saponin Contents?

Agriculture is facing many challenges, such as climate change, drought, and salinity, which call for urgent interventions for fast adaptation and crop diversification. The introduction of high-value and stress tolerant crops such as quinoa would be a judicious solution to overcome constraints related to abiotic stress and to increase land productivity and farmers’ incomes. The implementation of quinoa in Morocco has not been supported by a full valorization program to control the quality of quinoa seeds. The novelty of this work is to assess the pearling operation as an efficient method of saponins removal as well as the determination of total residual saponins. This study aimed to evaluate the effects of several pearling durations on nutrient and saponin content of quinoa seeds of three tested varieties (Puno, Titicaca, and ICBA-Q5). Five pearling durations were tested (0, 2, 4, 6, 7, and 8 min) using a locally manufactured pearling machine. The results indicated that a pearling duration of two minutes was enough to reduce total saponin content from 0.49% to 0.09% for Puno variety, from 0.37% to 0.07% for Titicaca variety, and from 0.57% to 0.1% for ICBA-Q5 variety. Our results showed that pearling slightly reduced protein, total fat, and moisture contents for all varieties except for Puno, where total fat content slightly increased with the pearling. Puno variety had the highest seed content in terms of protein and total fat; the ICBA-Q5 variety had the lowest. Titicaca had the highest bran content in terms of protein and total fat, ICBA-Q5 had the highest bran content in terms of ash and the lowest bran content in terms of protein and total fat, and Puno had the lowest bran content in terms of ash. Pearling had no significant effect on macronutrient contents in the processed seed, but it resulted in a very highly significant difference for most of them in the bran except for Mg and S. Regarding seed content in terms of micro-nutrients, statistical analysis showed significant differences between varieties in terms of Zn, Cu, and Mn contents, but no significant difference was recorded for Fe or B. Pearling had no significant effect on seed micronutrient contents. Therefore, to retain maximum nutritional content in the quinoa and maintain quinoa integrity, it is necessary to limit the pearling duration of quinoa to two minutes, which is enough to reduce saponin content below the Codex Standard threshold (0.12%).

Thresher for threshing of the individual sunflower heads

As a result of the studying the threshing process of individual sunflower heads on a specially designed stand, we found the main factor affecting the quality of threshing is the threshing disc speed. It is named the acceleration coefficient, which is defined as the ratio of the threshing roller frequency to the starting frequency. It allowed modifying the design of the existing thresher. While modernizing the thresher, the basic principle of sunflower heads threshing and threshing modes remained unchanged. We added a smooth adjustment of threshing modes by means of an electric motor speed control unit, which allows adjusting the thresher for high-quality threshing of heads of the various sunflower varieties. The deck is cleared of seeds stuck in it with compressed air; the threshed head is ejected automatically. According to the results of laboratory tests of the modernized thresher, it was concluded that it provides highquality threshing of individual sunflower heads. Therewith, amount of injured seeds does not exceed 0.35%, seed losses in the thresher do not exceed 1.73% and the seed content in the heap after threshing is 97.02 %.

The Complete Chloroplast Genome of Plukenetia volubilis Provides Insights Into the Organelle Inheritance

Plukenetia volubilis L. (Malpighiales: Euphorbiaceae), also known as Sacha inchi, is considered a promising crop due to its high seed content of unsaturated fatty acids (UFAs), all of them highly valuable for food and cosmetic industries, but the genetic basis of oil biosynthesis of this non-model plant is still insufficient. Here, we sequenced the total DNA of Sacha inchi by using Illumina and Nanopore technologies and approached a de novo reconstruction of the whole nucleotide sequence and the organization of its 164,111 bp length of the chloroplast genome, displaying two copies of an inverted repeat sequence [inverted repeat A (IRA) and inverted repeat B (IRB)] of 28,209 bp, each one separating a small single copy (SSC) region of 17,860 bp and a large single copy (LSC) region of 89,833 bp. We detected two large inversions on the chloroplast genome that were not presented in the previously reported sequence and studied a promising cpDNA marker, useful in phylogenetic approaches. This chloroplast DNA (cpDNA) marker was used on a set of five distinct Colombian cultivars of P. volubilis from different geographical locations to reveal their phylogenetic relationships. Thus, we evaluated if it has enough resolution to genotype cultivars, intending to crossbreed parents and following marker’s trace down to the F1 generation. We finally elucidated, by using molecular and cytological methods on cut flower buds, that the inheritance mode of P. volubilis cpDNA is maternally transmitted and proposed that it occurs as long as it is physically excluded during pollen development. This de novo chloroplast genome will provide a valuable resource for studying this promising crop, allowing the determination of the organellar inheritance mechanism of some critical phenotypic traits and enabling the use of genetic engineering in breeding programs to develop new varieties.