Seed behaviour in Phoenix reclinata Jacquin, the wild date palm

2004 ◽  
Vol 14 (2) ◽  
pp. 197-204 ◽  
Author(s):  
Gundula T. von Fintel ◽  
Patricia Berjak ◽  
N.W. Pammenter
Keyword(s):  
Date Palm ◽  
Water Concentration ◽  
Dry Mass ◽  
Developmental Study ◽  
Post Harvest ◽  
Palm Species ◽  
Embryo Cells ◽  
Orthodox Seeds ◽  
Pre Treatment ◽  
The Many

Despite the importance of the palm family, Arecaceae, little has been systematically documented about the seed behaviour of the many species. The post-harvest seed behaviour of Phoenix reclinata, the highly utilized wild date palm species distributed along the eastern seaboard of Africa, is investigated in the present study. While both embryo and endosperm water concentration declined as the seeds of Phoenix reclinata matured, they remained relatively high: this is a characteristic of (but not confined to) non-orthodox seeds. The ultrastructure of embryo cells, and the finding that negligible water uptake was required for the initiation of germination, were in keeping with the possible non-orthodox nature of the seeds. A developmental study revealed that between the acquisition of full germinability and complete pre-shedding maturity, germination performance appeared to be constrained, suggesting the presence of an inhibitor. Pre-treatment by soaking, mechanical or acid scarification had no significant promotory effect on either rate or totality of germination of mature P. reclinata seeds, while use of water transiently at 100°C was highly deleterious. However, germination of partially dehydrated seeds was initiated sooner if they had been soaked or scarified. Mature P. reclinata seeds tolerated dehydration to a mean embryo water concentration of 0.40 g g–1 (dry mass basis; dmb), but at 0.14 g g–1, both rate and totality of germination were adversely affected. However, viability of seeds dehydrated to the mean embryo water concentration 0.40 g g–1 declined during storage for 16 weeks. It is concluded that P. reclinata seeds are non-orthodox, and are best categorized as showing intermediate post-harvest behaviour.

An analysis of embryo development in palm: interactions between dry matter accumulation and water relations in Pritchardia remota (Arecaceae)

2012 ◽  
Vol 22 (2) ◽  
pp. 97-111 ◽  
Author(s):  
Hector E. Pérez ◽  
Lisa M. Hill ◽  
Christina Walters
Keyword(s):  
Water Relations ◽  
Desiccation Tolerance ◽  
Dry Matter ◽  
Cell Structure ◽  
Mechanical Strain ◽  
Seed Storage ◽  
Dry Mass ◽  
Dry Matter Accumulation ◽  
Palm Species ◽  
Embryo Cells

AbstractAssessments of seed storage physiology among Arecaceae (palm) species are often inconclusive because seeds exhibit diverse responses to low temperature and moisture conditions. Interrelationships between dry matter accumulation, cell structure and water relations during seed development of the endangered Hawaiian endemic palm, Pritchardia remota, suggest that damage from drying results from mechanical strain. Endosperm and fruits accumulate dry mass through most of the 400 d gestation period, but embryos reached maximum dry mass about 250 d post-anthesis (DPA). Mostly sucrose and some triacylglycerols accumulated in the cytoplasm and vacuoles of embryo cells, and organelles in mature embryo cells de-differentiated. Water content and water potential decreased as embryos matured and embryos contained about 0.45 g H2O (g dry mass)− 1 ( − 26 MPa) at shedding. Mature embryos survived drying to 0.16 g g− 1 ( − 49 MPa), but further drying was lethal. A model of allowable cell shrinkage is consistent with the substantial, but incomplete, desiccation tolerance acquired in P. remota embryos, and provides a new framework to explain variation in critical water contents as embryos develop. We suggest that desiccation tolerance, which distinguishes recalcitrant and orthodox physiologies among seeds, can be quantified by mechanical strain when embryo cells shrink during drying.

Relationships between cover performance and date of fall-seeding where winter rye was broadcast into a standing potato crop

1992 ◽  
Vol 72 (1) ◽  
pp. 269-274
Author(s):  
Linnell M. Edwards ◽  
John M. Sadler
Keyword(s):  
Cover Crops ◽  
Potato Crop ◽  
Ground Cover ◽  
Dry Mass ◽  
Winter Survival ◽  
Winter Rye ◽  
Winter Ground ◽  
Post Harvest

Winter rye was broadcast into a potato crop just after topkilling with the object of avoiding post-harvest delays in establishing a winter ground cover. Rye treatments were interseeded (i) at intervals of 1 d for up to 10 d before potato digging, without post-harvest tillage and (ii) just after digging and preparatory seedbed tillage as a comparative standard. Generally, cover performance of rye, measured as plant count, tiller count or dry mass of plants showed significant (P < 0.05) increase with decreasing days to potato digging up to 3 or 4 d before digging. There was no sacrifice of rye cover using this inter-seeding approach compared with traditional post-(potato) harvest seeding in a prepared seedbed. Seeding 3–4 d before potato harvest is recommended on the basis of superior fall plant count, spring tiller count and shoot dry mass, and winter survival indices on either of these days.Key words: Cover crops, winter rye, winter survival, companion cropping

scholarly journals Delignification of Date Palm Fronds using Modified Organosolv Technique

2017 ◽  
Vol 13 (3) ◽  
pp. 1-9
Author(s):  
Yasmeen Salih Mahdi ◽  
Asem Hassan Mohammed ◽  
Alaa Kareem Mohammed
Keyword(s):  
Date Palm ◽  
Lignin Content ◽  
Statistical Experimental Design ◽  
Digestion Time ◽  
Stainless Steel Reactor ◽  
Pre Treatment ◽  
Design Type ◽  
Palm Fronds ◽  
Central Composite ◽  
High Lignin Content

Abstract   In this study, modified organic solvent (organosolv) method was applied to remove high lignin content in the date palm fronds (type Al-Zahdi) which was taken from the Iraqi gardens. In modified organosolv, lignocellulosic material is fractionated into its constituents (lignin, cellulose and hemicellulose). In this process, solvent (organic)-water is brought into contact with the lignocellulosic biomass at high temperature, using stainless steel reactor (digester). Therefor; most of hemicellulose will remove from the biomass, while the solid residue (mainly cellulose) can be used in various industrial fields. Three variables were studied in this process: temperature, ratio of ethanol to water and digestion time. Statistical experimental design type Central Composite Design (CCD) has been used to find a mathematical relationship between the variables and the remaining lignin percent as dependent variable. The results obtained in this study were represented by a polynomial mathematical equation of the second degree.  The results showed that the best digestion time was (80 minutes), which gave the best percent remaining concentration of lignin (3%) at temperature of 185oC and ratio of ethanol: water equal to 50: 50 wt/wt. In order to reduce digesting time, the effect of using different catalysts have been studied such as (NaOH, H2SO4, Ca (OH) 2) at low concentration (0.025, 0.025, 0.05M) respectively. It was found that the best catalyst is sodium hydroxide at concentration (0.025) mol/L which gave the same percent of  lignin 3% but with low digestion time about 30 min. Keywords: Biomass pre-treatment, delignification, lignin, organosolv, date palm fronds.

scholarly journals Silicon Potential as Attenuator of Salinity Effects on Growth and Post-harvest Quality of Lettuce

2018 ◽  
Vol 10 (7) ◽  
pp. 455
Author(s):  
Hozano De Souza Lemos Neto ◽  
Marcelo De Almeida Guimarães ◽  
Rosilene Oliveira Mesquita ◽  
Italo Marlone Gomes Sampaio ◽  
Ana Régia Alves de Araújo Hendges ◽  
...  
Keyword(s):  
Plant Growth ◽  
Titratable Acidity ◽  
Dry Mass ◽  
Soluble Solids ◽  
Saline Stress ◽  
Post Harvest ◽  
Randomized Design ◽  
Salinity Levels ◽  
Completely Randomized Design

Silicon (Si) is a mineral element that provides many benefits to plants and may also assist in tolerance to abiotic stresses such as salinity. The aim of the study was to evaluate the use of Si as a possible attenuator of the deleterious effects of salinity on growth and post-harvest of lettuce. A completely randomized design with four replicates was performed in a 3 × 2 factorial, consisting of three salinity levels (1.65, 3.65, 7.65 dS m-1) and two levels of silicon (0.0 and 2.0 mM). Salinity reduced all variables related to plant growth. For shoot fresh and dry mass, it was observed that NaCl caused a reduction of 79.80 and 80%, respectively, in comparison to the control. However, parameters related to post-harvest such as titratable acidity, soluble solids and vitamin C increased with salinity. Although not effective in reducing saline stress on plant growth, Si provided improvements in the variables related to lettuce post-harvest. Salinity significantly reduced plant growth in the presence and absence of Si, but provided better post-harvest quality with Si.

A DEVELOPMENTAL STUDY OF WILD RICE, ZIZANIA AQUATICA L.

1960 ◽  
Vol 38 (5) ◽  
pp. 719-741 ◽  
Author(s):  
Cynthia E. Weir ◽  
Hugh M. Dale
Keyword(s):  
Wild Rice ◽  
Embryo Sac ◽  
Developmental Study ◽  
Abscission Layer ◽  
Potential Yield ◽  
Zizania Aquatica ◽  
History Of ◽  
Nuclear Changes ◽  
Well Differentiated ◽  
The Many

The life history of wild rice is traced from the appearance of the first submersed leaves in the spring until the seed of this annual plant is buried at the bottom of a lake in the fall. The characteristics of the three types of leaves are discussed. The change from the simple vegetative apex to the many-tipped, young inflorescence occurs early. Thus the potential yield in rice grains is determined as the tips of the upright leaves reach the surface of the water and before the stem elongates. The inflorescence develops acropetally as does each spikelet. Only at the later stages can the pistillate and staminate spikelets be distinguished. The development of the microspores and the nuclear changes in the embryo sac have been elucidated. In Zizania the embryo development has been found to be a variant of that found in Poa while the endosperm develops chiefly from the outside. A well-differentiated abscission layer develops at the base of each spikelet.

Assessing the toxicity of lead in sediments to Hyalella azteca: the significance of bioaccumulation and dissolved metal

1999 ◽  
Vol 56 (8) ◽  
pp. 1494-1503 ◽  
Author(s):  
Uwe Borgmann ◽  
Warren P Norwood
Keyword(s):  
Screening Tool ◽  
Water Concentration ◽  
Dry Mass ◽  
Overlying Water ◽  
Organic C ◽  
Complexing Capacity ◽  
Large Water ◽  
The Relationship ◽  
Pb Concentration ◽  
Body Concentration

The relationship between bioaccumulation and toxicity of Pb to Hyalella was the same for animals exposed to Pb in water alone and for those exposed to Pb-spiked sediments, provided that the animals were gut cleared before Pb analysis. The same critical body concentration (about 126 nmol·g dry mass-1) can be used to predict Pb toxicity in both water-only and sediment exposures. Furthermore, Pb bioavailability in Pb-spiked sediments was due primarily to dissolved metal: animals caged above the sediments accumulated the same amount of Pb and had the same mortality as animals exposed directly to sediment. Increasing the water to sediment ratio from 4:1 to 67:1 resulted in a lower dissolved organic C and lower total dissolved Pb concentration in the water but no change in bioavailable Pb (i.e., bioavailable Pb was not proportional to total dissolved Pb). The overlying water concentration may be a useful indicator of bioavailable Pb in sediment tests, provided a large water to sediment ratio is used to reduce the effect of sediment on overlying water quality (i.e., Pb-complexing capacity). Although less reliable than body concentration measurements, this could provide a useful screening tool for possible Pb-induced toxicity because it can be measured without test animals present.

scholarly journals Trapping-a major tactic of BIPM strategy of palm weevils

CORD ◽  
2005 ◽  
Vol 21 (01) ◽  
pp. 34 ◽  
Author(s):  
S. P. Singh ◽  
P. Rethinam
Keyword(s):  
Tamil Nadu ◽  
Date Palm ◽  
Elaeis Guineensis ◽  
Cocos Nucifera ◽  
Middle Eastern ◽  
Phoenix Dactylifera ◽  
Economic Losses ◽  
Palm Species ◽  
The Status ◽  
Cocos Nucifera L

Several species of curculionid weevils such as Amerrhinus ynca Sahlberg, Cholus annulatus Linnaeus, C. martiniquensis Marshall, C. zonatus (Swederus), Diocalandra frumenti (Fabricius), Dynamis borassi Fabricius, Homalinotus coriaceus Gyllenhal, Metamasius hemipterus Linnaeus, Paramasius distortus (Gemminger & Horold), Rhabdoscelus obscurus (Boisduval), Rhinostomus barbirostris (Fabricius), R. afzelii (Gyllenhal), Rhynchophorus bilineatus (Montrouzier), R. cruentatus Fabricius, R. ferrugineus (Olivier), R. palmarum (Linnaeus) and R. phoenicis (Fabricius) are associated with palms. Some of these have become a major constraint in the successful cultivation of coconut palm (Cocos nucifera L.), date palm (Phoenix dactylifera L.) and oil palm (Elaeis guineensis L.). R. ferrugineus is distributed in over 33 countries and attacks more than two dozen palm species. In the recent past, it has spread to Middle Eastern countries, Mediterranean region of Africa and southern Europe (Spain) causing tremendous economic losses. The yield of date palm has decreased from 10 to 0.7 tons/ha. Coconut palms in India are infested upto 6.9 per cent in Kerala and 11.65 per cent in Tamil Nadu. R. palmarum is a major pest of oil and coconut palms in the tropical Americas and, vectors the nematode, Bursaphelenchus cocophilus (Cobb) Baujard which causes red ring disease (RRD). Palm losses due to RRD are commonly between 0.1 to 15% which amounts to tens of millions dollars. The status of other species is briefed. The grubs of weevils that develop in the stems, bud, rachis of leaves and inflorescence of cultivated, ornamental or wild palms cause direct damage. Because of the cryptic habitat of the grubs, which act as tissue borer, the management becomes difficult.

scholarly journals EFFECT OF TRYPTOPHAN AND SOME POST HARVEST TREATMENT ON SOME CHEMICAL AND PHYSICAL PROPERTIES OF DATE PALM FRUIT (Phoenix dactylifera L.) C.V ASHRASSI: تأثير التربتوفان وبعض معاملات مابعد الحصاد في بعض الصفات الفيزيائية والكيميائية لثمار التمر (.Phoenix dactylifera L) صنف أشرسي

2019 ◽  
Vol 3 (3) ◽  
Author(s):  
Eman Hekmet Hassan  , Ghalib Nassir Hussein  ,   Nabeel Ibra
Keyword(s):  
Heat Treatment ◽  
Date Palm ◽  
Growing Season ◽  
Phoenix Dactylifera ◽  
Fruit Weight ◽  
Reducing Sugar ◽  
Total Sugar ◽  
Palm Fruit ◽  
Post Harvest ◽  
Phoenix Dactylifera L

    The study was conducted on date palm fruit (Phoenix dactylifera L.) c.v. Ashrassi, wich included tow experiment: first one field study carried out during the growing season 2017 at Mandali date palm station/ Ministery of Agriculture, the second one was A laboratory experiment conducted at Post harvest physiology lab at the Department of Horticulture and Landscape Grading/ College Agriculture University of Diyala,9 trees were selected at 10 years old homogeneous in size and growth planted at 5x5 m, The experiment was designed as factorial experiment using Complete Block Designed (RCBD), with two factor: tryptophan spraying at 0, 100, 200 ml. L- 1 concentration five times one spray each month, at Hababok stage, the second factor: some artificial ripening method to promote fruit Ripening, included (heat treatment at 20ºC for 10 minutes, freezing the fruit at- 18 ºC for 42 hours, and soaking the fruit in ethephon solution at 1000, 1500 ml. L- 1. The results can summarized as follow, The interaction between tryptophan spray with 200 ml. L- 1 and freezing the fruit gave the highest values for fruit weight, length and total sugar percent, also the interaction between tryptophan spray with 200 ml. L- 1 and soaking the fruit in ethephon solution at 1500ml.L- 1 resulted significant increase in reducing sugar percent.    

scholarly journals Use of Olive Mill Wastewaters as Bio-Insecticides for the Control of Potosia Opaca in Date Palm (Phoenix dactylifera L.)

2020 ◽  
Author(s):  
Abdelilah Meddich ◽  
Abderrahim Boutasknit ◽  
Mohamed Anli ◽  
Meriame Ait Ahmed ◽  
Abdelilah El Abbassi ◽  
...  
Keyword(s):  
Date Palm ◽  
Phenolic Content ◽  
Negative Impact ◽  
Phoenix Dactylifera ◽  
The North ◽  
Palm Trees ◽  
Phoenix Dactylifera L ◽  
Olive Mill Wastewaters ◽  
Pre Treatment ◽  
Olive Mill

The date palm is one of the most economically important perennial plants of the North Africa and in Morocco, where it is extensively cultivated for food and many other commercial purposes. Palm trees are threatened by many pests such as Potosia opaca newly identified in Morocco, especially in Marrakesh and Errachidia regions. In addition, olive mill wastewaters (OMW) are an environmental problem in olive oil producing countries such as Morocco. Generally, these effluents are drained into ecosystems without any pre-treatment. To reduce their negative impact and to get benefits in particular from their high phenolic content, OMW were used as bio-insecticides in crude form. The results showed that crude OMW were effective to control this pest causing a weight loss similar to Cordus insecticide (17% vs. 15%) and mortality almost similar to Kemaban insecticide. OMW’s biocide potential was related principally to their high phenolic content. Based on HPLC analysis, ten phenolic molecules were identified, including two which were revealed as the major monomeric phenolic compounds in OMW, 0.248 g/L of hydroxytyrosol and 0.201 g/L of tyrosol. In this chapter, the potential use of OMW as bio-insecticides for the control of P. opaca in date palm is discussed.

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