Early Growth Characteristics Research Articles

Variation law of micro-void distribution characteristics in early stage of spallation damage

The development trend of spallation damage mechanics is to construct a physical model that couples information with micro-mesoscale structure of materials, which also promotes the development of numerical calculation methods, experimental techniques and theoretical research. The mechanism responsible for plastic deformation and failure of structural metal materials at high strain rates is complex and ainfluenced by heterogeneities in the micro-mesoscale structure that comprises the distribution of grain boundaries, interfaces, and pre-existing densities voids. The distribution of these mesoscale heterogeneities can provide either strengthening behavior or void nucleation sites and influence spall failure behavior. Due to the lack of evolutionary information of micro-mesoscopic void distribution characteristics, the current spallation damage model is not only restricted in its application in extreme environments with high strain rates, high pressures, and shock, but also does not effectively provide some information about the correlation between material damage and final material fragmentation particle size, which is of very concern in engineering. Therefore, it is urgent to develop a spallation damage model that can reflect the variation law of micro-mesoscopic void distribution characteristics in damaged materials. The probability distribution function of void nucleation based on cosine function is given in this work by analyzing various influencing factors in the process of void nucleation, combining the characteristics of early void growth, and considering the convenience of analytical solution. The analytical calculation results of the new probability function of void nucleation are consistent not only with the results of the variation of void number with time calculated by molecular dynamics, but also with the experimental results of tantalum spallation in the early stage of damage development, that is to say, the new probability function of void nucleation can reflect the variation law of micro-void distribution characteristics in the early stage of spallation damage to a certain extent.

Effect of D-mannitol and Gibberellic Acid on Physiological Parameters, Early Seedling Growth Characteristics, and Some of the Most Important Chemical Components of Barberry (Berberis vulgaris L.)

Background: One of the important medicinal plants and agricultural products in Asia, particularly in Iran, is barberry, and both salinity and drought can cause osmotic or ionic imbalance in plant cells. In order to study the impacts of D-Mannitol and gibberellic acid on seed germination, physiological parameters, early seedling growth characteristics, and some of the most important chemical ingredients of barberry, one experiment is designed. Methods: The experimental design was Completely Randomized Design (CRD) with three replicates, and drought stress was done by D-mannitol at various stress levels, namely, 0 MPa, 40 MPa, and 80 MPa, and the reaction of studied cultivar was assessed on the basis of experimental characteristics associated to germination and seedling growth, and Gibberellic acid treatments were 0 mgL-1, 300 mgL-1, 600 mgL-1, and 900 mgL-1. Results: The effects of D-mannitol were significant in germination percentage, germination rate, seedling vigor index, chlorophyll a, total chlorophyll, leaf dry weight and total sugar. Experimental treatments such as germination percentage, germination rate, and total chlorophyll were also influenced by the application of gibberellic acid. The interaction between D-mannitol and gibberellic acid had significant effect on peroxidase activity. The highest germination percentage, germination rate, seedling vigor index, catalase activity, peroxide activity, and Chlorophyll a were obtained for 0 MPa application of D-Mannitol, followed by usage of 40 MPa, and 80 Mpa, respectively. The maximum total chlorophyll, relative water content, and leaf dry weight were also related to control treatment (0 MPa D-Mannitol), while the higher values of proline content, carotenoids and total sugar were obtained for 80 MPa application of D-Mannitol. The maximum values of germination rate, germination percentage, seedling vigor index, peroxidase activity, and chlorophyll a were related to control treatment (0 mgL-1 gibberellic acid), and the highest CAT activity was related to the application of 300 mgL-1 gibberellic acid. The highest total chlorophyll content and relative water content were related to 0 mgL-1 gibberellic acid, while the maximum praline content and leaf dry weight were obtained for the application of 600 mgL-1 and 0 mgL-1 gibberellic acid. There was not any significant difference in carotenoids between gibberellic acid treatments, while the application of 900 mgL-1 gibberellic acid obtained the highest value of total sugar of barberry. Conclusion: Conclusively, on the basis of the results, the application of 80 MPa D-Mannitol and 600 mgL-1 could be recommended as they can increase the absorption of nutrients and water.

Early Growth and Developmental Characteristics of Chinese Bahaba (Bahaba taipingensis)

Early Growth and Developmental Characteristics of Chinese Bahaba (Bahaba taipingensis)

Seed coating with minerals and plant growth-promoting bacteria enhances drought tolerance in fennel (Foeniculum vulgare L.)

The seeds of many plants, including fennel (Foeniculum vulgare L.), are tiny and have low food reserves. Therefore, planting them accurately in the soil to achieve optimal yields is challenging. The present research aimed to study the impact of bio-priming and seed coating on seedling and vegetative growth of fennel plants under drought stress. The experiments were conducted in laboratory and greenhouse conditions triplicate using a completely randomized design (CRD). These experiments applied mineral and biological coating treatments as the first factor and drought tolerance at three levels (0, −0.3, and −0.6 MPa) as the second factor. Perlite (P), Vermiculite (V), and Kaolin (K) were used as a mineral coating. The mineral coating mixture was P10V10K5. The numbers mean the material (gr) ratio based on the seed weight. Combinational treatments of seed coating were CHA0 + coating, PF56 + coating, T39 + coating, T36 + coating, and non-coating (as control). Pseudomonas fluorescens P.F56, P. fluorescens CHA0, and Trichoderma harzianum T36 and T. harzianum T39 were employed as biological treatments. Experimental results showed that at 0 and -0.3 MPa osmotic potential levels, the T39 + coated seeds had the highest percentage of seedling emergences. At the −0.3 MPa level, the T39 + coated seeds had an increased seedling emergence percentage by 24% compared to un-inoculated seeds. At all levels of drought stress, the CHA0 + coated treatment had the highest level of chlorophyll a content, CAT, and APX enzyme activity. Seed coating with CHA0 and T39 enhanced fennel's early vegetative growth and biochemical characteristics under normal and drought stress and mitigated drought stress.

Nanoparticles and magnetic field as novel elicitors improve seed germination and early growth of Mediterranean cypress

Abstract This study aimed to investigate the possibility of increasing the germination traits and early growth characteristics of Mediterranean cypress by applying nanopriming and magnetic field. To perform nanopriming, seeds were primed with nanochitin, nanochitosan and nanocellulose at a concentration of 1% for 2 h. For magnetopriming, the seeds were exposed to a magnetic field at three levels (20, 30 and 40 mT) for 1, 10 and 20 min and then sown. In combined treatment, the seeds were exposed to the magnetic field and then primed in nanoparticle solutions at the same treatments as mentioned earlier, and were planted. Non-exposed seeds were used as a control. The selected seed germination parameters (the percentage and speed of germination, stem and radicle length, collar root diameter, fresh and dry weights of the radicle and stem, number of leaves and leaf area) of young seedlings were examined. The interaction of nano × magnetic resulted in significant differences in the number of leaves, leaf area, length of the radicle, length of the stem, fresh weight of the radicle, fresh weight of the stem and stem dry weight traits. The results showed that among all the applied treatments, 10 min magnetism to 20 mT and then priming with 1% solution of nanocellulose was the best. It increased the germination percentage (1.31 times), germination rate (1.46 times), number of leaves (1.57 times), leaf area (1.36 times) and radicle length (1.74 times) compared to the control (no treatment). A 20-min treatment under a 30-mT magnetic field (without nanoprime) is also recommended.

Survivorship and Field Growth Characteristics of Four Selected Bamboo Species for The Development of Bamboo Industry in Sarawak, Malaysian Borneo

The Sarawak State Government has assigned the Sarawak Timber Industry Development Corporation (STIDC) to lead the development of the bamboo industry in Sarawak. Since bamboo research in Sarawak has received meagre attention, baseline information on the early survival rate and field growth characteristics of bamboo are essential for the development of the bamboo industry. A study to evaluate the survivorship and field growth characteristics of a three-year-old bamboo was conducted at the Sarawak Bamboo Pilot Project site in Sabal, Malaysia. Study plots were established at bamboo plantation areas with four different potential bamboo species grown in Sarawak, namely Bambusa vulgaris (Buluh minyak), Gigantochloa levis (Buluh beting), Gigantochloa hasskarliana (Buluh beti), and Dendrocalamus asper (Buluh betong). Survival rate and field growth characteristics in terms of the number of culms per clump, the number of new shoots, culm diameter, culm height, mean annual increments of diameter (MAID), and height (MAIH) were measured and quantified quarterly in the year of 2021. The findings revealed that the highest mean survival rate (88%) was found in G. levis, and the lowest survival rate (70%) was found in G. hasskarliana. However, the lowest mean culm diameter was observed in G. levis at 2.66 cm, and the highest was in B. vulgaris at 4.51 cm. Notwithstanding, B. vulgaris remained with the greatest mean culm height of 12.61 m. Nonetheless, G. hasskarliana depicted the highest number of culms per clump and shoots with 91 culms and 3 shoots, respectively. The MAID and MAIH of B. vulgaris were significantly higher than the other species with 1.69 cm year-1 and 4.72 m year-1, respectively. The scientific information and findings from this study would be useful as guidelines for bamboo industry players, managers, nursery practitioners, and policymakers to begin and carry out the development of the bamboo industry, mainly in Sarawak.

Little or no maize (Zea mays) grain yield loss occurred in intercrop with mid‐maturity lablab (Lablab purpureus) in northeastern Tanzania

AbstractIntercropping is among sustainable intensification tactics farmers may use to increase or maintain productivity and environmental quality. Effects of planting lablab [Lablab purpureus (L.) Sweet] 1 or 2 weeks after planting maize (WAPM) are not well characterized, especially when mid‐maturity lablab cultivars are used. Greenhouse (Springfield, MO) and field studies (Arusha, Tanzania) were conducted in 2018 and 2019 to assess early (≤60 days) and full‐season effects on growth and grain production. The greenhouse study characterized early growth characteristics when lablab was sown 0, 1, or 2 WAPM for each of four cultivars of lablab. “Echo Cream” lablab produced greater vine length and more nodes than other cultivars in the greenhouse. Greenhouse lablab biomass and node number were greatest when sown ≤1 WAPM. The field study compared monoculture and intercrop grain yields. Highest maize yields occurred when lablab was sown ≥1 WAPM, but highest lablab yields occurred when planted at the same time as maize. The maize/lablab intercrop always resulted in favorable land equivalent ratios (LERs) ranging from 1.5 to 2.1. The partial LER of maize yield was not reduced by more than 7% relative to monoculture either year. Lablab yield was negatively affected by planting delay, decreasing about 60% in 2018 and 31% in 2019 in the 2 WAPM planting date treatment. Although twining lablab vines complicate grain harvest, our results demonstrate increased grain production per unit area with maize/lablab intercropping, with a potential for increased farmer income and household nutrition.

Fluid-based microbial processes modeling in Trichodesmium colony formation

In tropical and subtropical ocean gyres, Trichodesmium colonies account for up to half of the total N2 fixation in the ocean, making it one of the most ecologically significant N2-fixing cyanobacteria. The processes whereby Trichodesmium colonies and large-scale surface blooms form have not been investigated thoroughly. In particular, the effects of fluid motion have not been included in previous studies. As the first step toward understanding the mechanical processes associated with Trichodesmium colony synthesis, we propose a shear-related flow-based growth model to enlighten how fluid dynamics affect bacteria colony formation and growth. To investigate the possibility that early growth characteristics are strongly dependent on the shear rate, a two-way coupled fluid-colony interaction is developed using the lattice Boltzmann method for a porous colony. This model captures the exponential growth trend during the colony formation phase found in experiments. Our results show that the flow field significantly impacts both the colony growth rate and shape. In pure shear conditions, colonies grow in circular shapes, whereas in uniform flow, they take filament-like forms. Additionally, the Reynolds number (Re) plays a crucial role in shaping the colonies, especially in uniform flow conditions where its effect is more profound.

Early life growth and developmental trajectory in children with biliary atresia undergoing primary liver transplantation.

To clarify the early growth and developmental characteristics of children with biliary atresia (BA) undergoing primary liver transplantation (pLT). A prospective cohort study, which specifically focused on BA-pLT children, was conducted after the diagnosis of BA by following the children at the time of pLT and 1, 3, 5, 7 months and 1 year after pLT for growth and developmental monitoring. The growth parameters were calculated according to the WHO standard, and the developmental status was assessed using Denver Developmental Screening Tests. A total of 48 BA children who received pLT at the age of 5.00 ± 0.94 months were analyzed. The weight-for-age Z-value (ZW) and length-for-age Z-value (ZL) were higher than the head circumference-for-age Z-value (ZHC) at pLT (P = 0.002 and 0.02), but they were all lower than the WHO growth standard (Z = 0) (P < 0.001). The ZW and ZHC decreased first and then returned to the population level at 1 year after pLT, while the ZL only returned to the preoperative status and was lower than the ZW and ZHC (P < 0.001). Developmental screening showed that 35% (17/48) of the children were defined as suspicious and 15% (7/48) were abnormal at 1-4 months after pLT, the most likely time to be suspected of developmental delay. At 1 year after pLT, gross motor skill delay still existed (12/45, 27%), and language skill delay began to appear (4/45, 9%). BA-pLT children suffer from growth and developmental problems. Low ZHC is the main growth problem before pLT, while low ZL is the problem after pLT. Developmental delays are significant after pLT, especially in motor and language skills. The current study suggested that further studies are warranted to clarify the long-term growth and developmental outcomes of BA-pLT children, to compare them with children undergoing the Kasai procedure and to explore their influencing factors and possible mechanisms.

Long coleoptile genotype and soil texture interactions determine establishment success and early growth parameters of wheat sown at depth

Long coleoptile (LC) - wheat genotypes sown deeper (> 10 cm) than current practice (< 5 cm) enables earlier deep sowing into subsurface soil moisture. The LC genotype shows promise to broaden sowing windows and remove reliance on the shifting seasonal break for crop establishment. The suitability of this sowing strategy to the highly variable soils of the southern Australian wheatbelt warrants investigation to identify suitable environments for potential establishment benefits. We conducted controlled environment room (CER) and field experiments using pairs of near-isogenic-lines (NILs) that differed genetically only for coleoptile length. The experiments investigated the suitability of deep sown (12 cm) LC wheats in soils with different texture (sand versus loam). The CER experiment identified that LC genotypes exhibited greater emergence and early seedling growth, producing greater shoot and root biomass, when deep sown (12 cm) in loam. While LC and short coleoptile (SC) genotypes produced similar shoot growth when sown at depth in sand, LC produced greater root biomass reflected in more seminal roots. In the field on sand, LC and SC had similar emergence and early shoot growth characteristics at all sowing depths (5, 8 and 10 cm). However, the heavy-textured, loam soil reduced seedling emergence and restricted leaf growth with deep sowing (12 cm) in the SC. Our results indicate that the LC trait was more critical for plant emergence and early growth parameters (shoot and root biomass) from depth in a heavier textured loam compared with a sand. By identifying environments that will likely benefit most from deep sown LC, we are one step closer to adapting crop production to shifting rainfall patterns in southern Australia.

Allelopathic potential of Codiaeum variegatum L. Rumph. Ex A. Juss. On germination, early growth and biochemical characteristics of Lolium perenne L

Allelopathic potential of Codiaeum variegatum L. Rumph. Ex A. Juss. On germination, early growth and biochemical characteristics of Lolium perenne L

Clonal variations in seed characters and germination in Hevea brasiliensis

The principal form of dissemination for most plant species is seeds, an important source of biodiversity conservation. For rubber plantations, seeds are the initial material for seedling production. In Cameroon, there is limited information related to clonal seed characterisation and early growth performance. This study sorts to characterise Hevea brasiliensis seeds from GT 1, PR 107, PB 217, PB 235, and PB 260 clones and evaluate the germination rate and seedling early growth characteristics to enable planning for nursery management. Clone GT 1 had the highest seed length (3.98 cm), seed kernel weight (3.4 g) and total seed weight (4.75 g). Clone PB 235 had the heaviest shell (1.96 g). There was no significant correlation between seed size, germination percentage and early seedling growth for the different clones. Clone PR 107 had the lowest per cent seed germination, with just 55 per cent of its seed germinating after two weeks, whereas clone PB 217 had the highest seed germination (92.5%). Seedling height, seed germination percentage and shell weight were significantly correlated. The results of this study provide some useful information for rubber nursery managers.

Growth trajectory during the first 1000 days and later overweight in very preterm infants

ObjectiveTo identify the characteristics of early life growth associated with later overweight or obesity (OWO) in very preterm population.DesignLength, weight and body mass index (BMI) were prospectively recorded from three...

Interactive effects of light and snail herbivory rather than nutrient loading determine early establishment of submerged macrophytes.

Submerged macrophytes play a key role in maintaining a clear‐water phase and promoting biodiversity in shallow aquatic ecosystems. Since their abundance has declined globally due to anthropogenic activities, it is important to include them in aquatic ecosystem restoration programs. Macrophytes establishment in early spring is crucial for the subsequent growth of other warm‐adapted macrophytes. However, factors affecting this early establishment of submerged macrophytes have not been fully explored yet. Here, we conducted an outdoor experiment from winter to early spring using the submerged macrophytes Potamogeton crispus and Vallisneria spinulosa to study the effects of shading, nutrient loading, snail herbivory (Radix swinhoei), and their interactions on the early growth and stoichiometric characteristics of macrophytes. The results show that the effects strongly depend on macrophyte species. Biomass and number of shoots of P. crispus decreased, and internode length increased during low light conditions, but were not affected by nutrient loading. P. crispus shoot biomass and number showed hump‐shaped responses to increased snail biomass under full light. In contrast, the biomass of the plant linearly decreased with snail biomass under low light. This indicates an interaction of light with snail herbivory. Since snails prefer grazing on periphyton over macrophytes, a low density of snails promoted growth of P. crispus by removing periphyton competition, while herbivory on the macrophyte increased during a high density of snails. The growth of V. spinulosa was not affected by any of the factors, probably because of growth limitation by low temperature. Our study demonstrates that the interaction of light with snail herbivory may affect establishment and growth of submerged macrophytes in early spring. Macrophyte restoration projects may thus benefit from lowering water levels to increase light availability and making smart use of cold‐adapted herbivores to reduce light competition with periphyton.

Nitrogen modulates early growth and physio-biochemical attributes in fragrant rice grown under cadmium and multiwall carbon nanotubes stresses.

Nitrogen (N) modulates plant growth, but its impact on the early growth and physio-biochemical characteristics of rice under cadmium (Cd) and multiwall carbon nanotubes (MWCNTs) toxicity has received little attention. In this study, a hydroponic experiment was conducted on two fragrant rice cultivars, e.g., Xiangyaxiangzhan (XYXZ) and Yuxiangyouzhan (YXYZ), grown under two N levels (N and 1/4N) and various Cd and MWCNTs treatments (CK: without CdCl2 or MWCNTs; Cd: 100μmol L-1 CdCl2; MWCNTs: 100mg L-1 MWCNTs; and Cd-MWCNTs: 100μmol L-1 CdCl2 + 100mg L-1 MWCNTs). Results showed that when compared to CK, the total dry weight of the Cd and MWCNTs treatments did not change under 1/4N for both varieties, whereas Cd and Cd-MWCNTs treatments resulted in a significant reduction in total dry weight by 18.78-37.85% for XYXZ and the Cd-MWCNTs treatment resulted in a significant reduction in the total dry weight by 20.24% for YXYZ. The changes in total dry weight were linked to changes in the dry weight of the different parts of the plant. Besides, the antioxidant parameters and the enzymes involved in the nitrogen metabolism changed in different varieties and different plant parts under two N levels and various Cd and MWCNTs treatments. In addition, differences in total dry weight changes at the N levels and various Cd and MWCNTs treatments were identified between the two varieties, and the relations between total dry weight and other investigated parameters indicated that the modulation processes varied between varieties. Overall, N modulates the early growth and physio-biochemical attributes in fragrant rice seedlings under Cd, MWCNTs, and their combined toxicity.

Combined effects of intake oxygen enrichment, intake pressure and temperature on combustion behavior and emission characteristics of a small-scaled rotary engine

Intake oxygen enrichment has a promising potential to improve the combustion performance of a small-scaled rotary engine (RE) operating at high altitudes. However, the process is complicated because the intake temperature and pressure are sensitive to altitudes as well as the elongated rotor chamber. In this study, a three-dimensional CFD simulation model coupling with a suitable turbulent model and a reduced chemical kinetic mechanism was established and validated. The combined effects of intake oxygen enrichment as well as intake pressure and temperature under different altitudes on early flame growth, combustion behavior, and emission characteristics of small-scaled REs were numerically investigated. Results showed that intake oxygen enrichment promotes the formation of OH, O, H radicals, which leaded to the significant improvements of the early flame growth, especially for the flame near leading spark plug. The promotion effect due to intake oxygen enrichment became weak with increasing altitude. Moreover, the early flame growth duration at high altitudes was more dramatically shortened by intake oxygen enrichment than that at low altitudes. It is interesting to note that when oxygen concentration of 25% and 29% were applied to the small-scaled RE working at 2000 m and 3000 m altitude, respectively, the engine performance could be restored to the level of that working at sea level at the price of a smaller increment of NO emissions. Under high intake oxygen concentration conditions, the effect of altitude on indicated thermal efficiency of the engine could be ignored. Besides, increasing oxygen concentration significantly reduces HC and CO emissions, especially more significant reduction for HC emissions at higher altitudes. • Early flame growth of the rotary engine was analyzed numerically. • Early flame growth near LSP was more significantly improved by oxygen enrichment. • Effect of intake oxygen enrichment on rotary engine performance was quantified. • Oxygen enrichment significantly reduced HC and CO emissions.

EFFECT OF SEED PRE-SOWING TREATMENTS ON THE GERMINATION AND EARLY GROWTH OF ALBIZIA LEBBECK SEEDS

Albizia lebbeck is a multipurpose tree that has many benefits for the environment and the end user. The extent to which this tree species is cultivated is very low due to seed coat dormancy, which causes a longer germination period and late seedling growth. This research was done at Kwame Nkrumah University of Science and Technology, located in Kumasi, Ghana, at the Department of Horticulture, to ascertain the effect of seed pretreatment on germination and early seedling growth. Germination was observed in seeds pretreated with hot water (100º) for 1 minute (T1), dry heat (90º) for 2 minutes (T2), in 6% hydrogen peroxide solution for 30 minutes (T3), cold water at room temperature for 24 hours (T4) and untreated seed (T5) as the control. The experiment was conducted using a randomised complete block design (RCBD) with three replications. The data obtained for seed germination percentage were statistically analysed using one-way analysis of variance in Statistix 7.0 software, and the least significant difference at 5% probability level was used to separate the means of height, collar diameter and number of leaves. A comparison between the pretreated and control seeds showed no significant difference (P &gt; 0.05) on germination percentage, germination rate, and root and shoot dry weights of Albizia lebbeck. However, it had a positive influence (P &lt; 0.05) on early growth characteristics. Seeds soaked in cold water (T4) had maximum early seedling growth. Hydrogen peroxide treatment (T3) yielded the highest collar diameter growth. Hot water treatment (T1) had the lowest height, collar diameter and number of leaves. Cold water at room temperature should be encouraged as a pretreatment method for the early growth of Albizia lebbeck seedlings.

Genetic Analysis of Early Growth Characteristics in a Pistachio (Pistacia vera L.) Population Raised under Greenhouse Conditions for use in Breeding Program

Genetic Analysis of Early Growth Characteristics in a Pistachio (Pistacia vera L.) Population Raised under Greenhouse Conditions for use in Breeding Program

Study on the Early Growth Characteristics of Kandelia candel Plantation in Yanpu Bay, Cangnan, Zhejiang Province

Study on the Early Growth Characteristics of Kandelia candel Plantation in Yanpu Bay, Cangnan, Zhejiang Province

Breeding Polyploid Varieties of Acacia: Reproductive and Early Growth Characteristics of the Allotetraploid Hybrid (Acacia mangium × A. auriculiformis) in Comparison with Diploid Progenitors

Diploid clones of the hybrid acacia (Acacia mangium × A. auriculiformis) are widely planted in Vietnam because of their high productivity, adaptability, and commercial wood yields. Polyploid breeding offers possibilities for further enhancing hybrid vigor and generating new high value genotypes. In a field trial, we compared three diploid hybrid clones with their respective colchicine-induced tetraploid lines. Flowering and seed production of each cytotype were observed and open pollinated seed collected for determination of outcrossing rate and ploidy, inbreeding depression and marker inheritance in the progeny. Comparisons are also made with published characteristics of autotetraploids derived from A. mangium. Compared with their corresponding diploid cytotypes, the allotetraploids flowered slightly later but more intensely; produced the same number of seeds per pod but larger seeds; and showed a greatly reduced level of outcrossing (an average of 14% compared with 87%). Inbreeding depression for height growth was less for progeny from the allotetraploid lines (17%) than for those from the original diploids (33%). 96% of seeds from the allotetraploid clones were also tetraploid, but we observed triploids at low frequency at both the seed and field progeny stages. The segregation of the molecular markers in outcrossed allotetraploid progenies demonstrated both disomic and tetrasomic inheritance, indicating that the hybrid behaves as a segmental allotetraploid. Results suggest that an open pollinated breeding strategy is a practical option for improving polyploid acacia hybrids.