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( • ) ! ! ,-. % ! / % 01. ! ! ! !! * • 2112 % ( •% •# • •7 • ! • " # 2 34,1& 5 2111& ! * " ! ! ! ! 6 + 3 6 ! ! * &+ • Constants Our World – 36.6 billion hectares of ocean – 14.7 billion hectares of land • 6.4 b ha without significant biomass • 8.3 b ha with significant biomass • Variables – Population – Productivity Changes Through the 20th Century Year Population 1940 2.3 billion 1970 3.7 billion 2000 6.1 billion 2.7x 3600 m ha 3.6x 3.8 t/ha 3.3x Changes through the 20th Century Year Population 1940 2.3 billion 1970 3.7 billion 2000 6.1 billion Area in production Average yield 990 m ha 1450 m ha 1.15 t/ha 1.7 t/ha Area in production Total Average production Ave. yield 990 m ha 1139 m t 1.15 t/ha 1450 m ha 2455 m t 1.7 t/ha 3600 m ha 13680 m t 3.8 t/ha $% Rising standard of living = more meat consumption Caloric conversion Animal/product Dairy (cow) Beef Pig Sheep Chicken Eggs Chicken (Broilers) Turkey Feed consumed/Unit of production (as corn, US year 2000 statistics - USDA) 73 lb/ 100 lb milk 1259 lb/ 100 lb 596 lb/100 lb 1613 lb/ 100 lb (includes weight of wool) 52 lb/ 100 eggs 235 lb/100 lb 380 lb/100 lb Challenges for the 21st Century Year Population % food insecure Area in production Average yield 1940 2.3 billion -990 m ha 1970 3.7 billion 37% 1450 m ha 2000 6.1 billion 18% 3600 m ha 2030 8.1 billion ? ? 1.15 t/ha 1.7 t/ha 3.8 t/ha ? t/ha Challenges for the 21st Century 1.40E+10 1.20E+10 1.00E+10 8.00E+09 6.00E+09 4.00E+09 3.8 t/ha 2.00E+09 1.15 t/ha 0.00E+00 1940 1.7 t/ha 1970 Year 2000 Population Cultivated area (ha) Production (mt) Challenges for the 21st Century Year Population % food insecure Area in production Average yield 1940 2.3 billion -990 m ha 1970 3.7 billion 37% 1450 m ha 2000 6.1 billion 18% 3600 m ha 2030 8.1 billion ? 4900 m ha Yield, t/ha 1.15 t/ha 1.7 t/ha 3.8 t/ha ? t/ha Consider Land as a Variable 8.3 billion hectares with significant biomass • • • 1.3 b ha traditional farmland 3.5 b ha traditional grasslands 3.5 b ha traditional forests – (where traditional means through history/before 1960) Challenges for the 21st Century Year Population % food insecure Area in production Average yield 1940 2.3 billion -990 m ha 1970 3.7 billion 37% 1450 m ha 2000 6.1 billion 18% 3600 m ha 2030 8.1 billion ? 4900 m ha 3.6 b ha are under production as of 2000, taking over traditional grassland/forests 4.9 b ha are potentially arable • • • enough topsoil sufficient growing season access to water 1.15 t/ha 1.7 t/ha 3.8 t/ha ? t/ha Challenges for the 21st Century 1.40E+10 Population Cultivated area (ha) Production (mt) 1.20E+10 Traditional Farmlands Were Used for a Reason • Many traditional farmlands have adequate water, soil fertility • Some traditional farmlands were used out of necessity, with consequences to yield due to soboptimal soils • Many new farmlands are on even more marginal soils 1.00E+10 Yield, t/ha 8.00E+09 6.00E+09 Max arable land on planet 4.00E+09 3.8 t/ha 2.00E+09 1.15 t/ha 1940 1.7 t/ha 1970 Year 2000 ?? t/ha 0.00E+00 2030 Defining the problems • Abiotic stresses – Water – Temperature – Soil conditions • Salt, pH, low nutrients or high levels of toxic metals Working Towards Solutions • Learn more about how plants tolerate environmental stresses and acquire essential mineral nutrients (physiology). • Identify the genes underlying the tolerance trait of interest. • Use this knowledge to improve crop plants and food security via molecular breeding, or biotechnology. • Biotic stresses – Disease – Pests Plant Stress Contributes to Human Stress • 16% of arable lands are “free of constraint” • Stress reduces potential yield 30-100% • Majority of crops do not produce at maximum potential • 825 million people are food insecure (not enough calories per day) Acid Soils Are a Global Problem • Acid soils due to millions of years of leaching in high rainfall areas. Leaches the base cations (Ca2+, Mg2+, K+) leaving an excess of H+ behind. • ~50% of worlds potentially arable soils have pH < 6 and ~1/3 have pH < 5. • Low soil pH solubilizes a toxic form of aluminum, Al3+, from aluminosilicate clays. Al3+ is highly toxic to plant roots (more about Al toxicity later). • The other major problem on low pH soils is phosphorous (P) deficiency. & ( & . / *&+ ,- % ) & ' • • ! 8 * 6 + $ ! *+ *+ • Low availability of soil P makes it the most limiting mineral nutrient for crop production worldwide. • On acid soils, P is the least available macronutrient as phosphate ions are tightly bonded to surface of clay minerals, particularly Fe and Al oxides. • On high pH (calcareous soils), P is tied up with calcium carbonates in the soil. • Also soil microbes compete with plant roots for soil P, converting Pi to organic P. • Hence plants have evolved some very interesting strategies to acquire P from the soil. • Raw material used for producing P fertilizers will not last forever. Estimated that P fertilizer reserves may run in next 50-100 years. • Thus scientists are studying the mechanisms plants use to acquire P in order to use this knowledge to improve crop P acquisition. 9: *+ 2-. ; *+ < * =! <= * 211>+ + ( 2?@3,-4 3,?? 8 " B # C B C B 6# 211> (D # ?@ 201 ( 8 " $! 7 A; * + *1 + *21 + >1 •( = 3 •= 7 7 5 3 2 ! 932: ; B #8 2 *; B2+ 8D D " % $ =7=( % 8 E=? *8" $ ?+ =8= D B7 * =8+ < 8 5 4&5 50 40 CH8 • 8 F $ B *C+ 30 20 10 9: 8 F= 0 0-6 cm 6-20cm >20cm • 110 4&5 + 100 • ! G * 9: $ 8 F% 90 80 Shallow Deep ! * 011$ 2 0113 - 8 5 8 I 5 ! I ! ! ! !! 7 I 7 7 ! #$ * 6 2-. 5 (+ *3404+ ( I I 8 • • • J E ! ! + 8< 6 ! ! ! *K $ 8 K! C + 5 ( ( = (* * + ! =( M 7N ! 6 MC "L (N ( * 2112+ "L E " 9 D A: D A2 "L! 6 "L 324@-1 ?> Proteoid Roots are Very Active in Modifying the Chemical Environment of the Soil (Neumann G, Martinoia E. 2002. Trends in Plant Science 7: 162-167) • • • •/ ! 7 " 3 *+ * P" & 7 . 89 . 6 & & 6 + * " A 1O " * +8 C% E 6 " PA * +8 7 >L B 7 7 2L 7 2L *# $ + P3 *+ B P3 - -+ 7 >L *+ ( *B ! P13 6 G 6 8 *A + 6 + * +$ " 2 6 C * * < C + 2112 % ,@ 3?2+ 6 6 • ALUMINUM TOXICITY AND ACID SOILS I ! :& 2-; -; : ! # " : ! 9 / !: & : ( ! :< 7 3> 3> I ! / : ! ! ! ! : 5 I I+ !: <1= : " I; ? 9@ ? 9 ;+ A@ @ @ ( ;B ( @ % & >L (; H Al Toxicity Reduces Crop Yields ATLAS $ ! 8% B 8 0 5 20 50 10 cms µM Al3+ # 6F $E ! = C6 8 ; ! ! SCOUT * Plants grown for 4 days & ! Malic Acid (µmoles flask -1) C@ ? ( ; 0.4 + % (@ @ A? ( ;@ ( @ +( 9@ E Root Growth (mm) 9 Tolerant 0.2 20 10 Tol (SA3) Sens (SA5) - Al + Al I I@ / C ! / D C / Sensitive 0 10 Citrate (pmol apex-1 hour-1) Hours 20 150 100 50 0 0 Malic Acid (µmoles flask -1) 1.5 Tolerant 0.5 0 Sensitive Al added (µM) 7 * $FF3- & $136GF< 100 200 & & & Hours * $FF<- & $FG6HII 6 12 18 Triticum aestivum (wheat) Plant Species name) (common Genotype Line ET3 Atlas 66 Chinese Spring and derived ditelosomic lines Kitakami B SA3 IAC-TAIUBA Cateto-Colombia ATP-Y Sikuani DK789 Malate Malate Malate Organic Acid Reference Released (Ryan et al. 1995a) (Delhaize et al. 1993a; Delhaize et al. 1993b) (Huang et al. 1996; Pellet et al. 1996) (Papernik et al. 2001) (Ishikawa et al. 2000) (Pellet et al. 1995) (Jorge and Arruda 1997) (Pineros et al. 2002) (Kollmeier et al. 2001) (Kidd et al. 2001) (Ishikawa et al. 2000) (Zheng et al. 1998a) (Li et al. 2000) (Ishikawa et al. 2000; Ma et al. 2002) (Magalhaes 2002) (Ma et al. 2000) (Ma and Miyasaka 1998) (Delhaize et al. 2001) (Ishikawa et al. 2000; Ma et al. 1997b) (Silva et al. 2001) (Yang et al. 2000) (Saber et al. 1999) (Ma et al. 1997c; Zheng et al. 1998a; b) (Zheng et al. 1998a) (Zheng et al. 1998a) (Kayama 2001) (Hoekenga et al. 2003b) (Schöttelndreier et al. 2001) ! ( ; ! Zea mays (maize) Avena sativa (oat) Secale cereale (rye) Oryza sativa (rice) Sorghum bicolor (sorghum) Triticale ssp (triticale) Colocasia esculenta (taro) Nicotiana tabacum (tobacco) Cassia tora (sickle senna) Glycine max (soybean) Helianthus annuus (sunflower) Fagopyrum esculentum (buckwheat) Raphanus sativus (radish) Brassica napus (rape) Miscanthus sinensis Anderss. and Miscanthus sacchariflorus Arabidopsis thaliana Galium saxatile (heath bedstraw) Citrate Citrate Citrate Citrate Citrate, Oxalate Citrate Citrate, malate Citrate, Malate Citrate Citrate Citrate,Malate Oxalate Citrate Citrate Citrate Citrate Citrate, Malate Oxalate Citrate, malate Citrate, malate Citrate Malate Citrate 7 % SC283 and derived NILs PI 416937 Suzunari C 211, < ; >4@ 33-? *C =+ 9 @ 10 9 8 7 6 5 4 3 2 1 0 ! *J ! C ; + 2 11H/ 0I3 SC283 B ! 2 ! ! 9 63<, @ *; / M 988O4 84e7 181g10 AltSB ISU52.2 0.6 cM CTG29 0.2 cM T755 M181 ) ! 1I 9 & 99b3 250h7 55D12 2 BR007 Frequency ! 01I< .06 11H/ 0I3 2 0H &! 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50 50-55 55-60 60-65 65-70 70-75 75-80 6 SNP G/A 1 2 1 3 4 7bp indel 5 2 (recombinants) 6 1 MITE 78 0 9 1 AltSB 10 SNP G/A 11 4 12 13 M181 14 15 16 10kb $$1 I ! ! 0, G 9C$ ! .063 .0 CTG29 17 1 0$/ AltSB: ORF7 8 G/ 5-10 T_ 0-5 ;! <$3 ;C& 9 1kb 0, G Relative Expression % of control (-Al) root growth + .H6 ! / . ;/ 69 ; 140 120 100 80 60 40 20 0 ATG TGA % CC $6 $ 06 J,I * 0J3 1 $1K&K1 0<χ 9! ! 011, & ! % @ !! L $GH6 $F1<C$F$, ! / ! L! 6 9 + .I + .F ;C& +.I F C> C> C> C> C> C> C> C> ; *1C$+ + + + + +++ ; *$C3- ; *3C</* - ; 8B (0 8B A (2 l) 010 7 A 1c B l) 0 m 10 (0 A -1 B(2 l) cm 7 0-1 8B Al) cm (0 0-1 8B A c (2 l) 1 m 7 10 Al) -3cm B 1 10 (0 A -3c B(2 l) m 7 1-3 8B Al) cm (0 1-3 8B A cm (2 l) 37 10 A 5cm B l) 10 (0 A 3-5 B(2 l) cm 7 3-5 8B Al) cm (0 3 8 B A -5cm (2 l) s 1 0 7 A hoo ts B l) 10 (0 A sho B(2 l) ots 7 sho Al) o s h ts oo ts Al: Lines: Tissue: S T roots (0-1cm) S T roots (1-3cm) S T roots (3-5cm) S T shoots ! 2 C#& / 9 9;. ! ;/ 2 $!<$3,1 + ( &G<001 2 $!<$3,1 + ( &G<001 2 $!<$3,1 + ( &G<001 2 $!<$3,1 + ( &G<001 2 Verifying That MATE Gene Family Member Is AltSB $!<$3,1 + ( &G<001 2 $!<$3,1 + ( &G<001 2 $!<$3,1 + ( &G<001 2 $!<$3,1 + ( &G<001 Physiology of Sorghum Al Tolerance Al tolerance is Al-Inducible 30 25 20 Temporal Expression Pattern of AltSB Candidate in Root Tips of Al Tolerant and Sensitive NILs Root Tip Citrate Efflux is AlInducible and Activated by Al 1200 1000 ATF 10B (Tolerant) ATF 10B (Tolerant) 140 Relative Expression Root citrate exudation (pmol plant h ) Root growth rate (mm d-1) 15 10 5 0 25 20 15 10 5 0 Control +27 µM Al -1 -1 800 600 400 200 0 1000 800 600 400 200 120 100 80 60 40 20 0 Vera Alves ATF 8B (Sensitive) ATF 8B (Sensitive) Control + 27 µM Al J B Jon Shaff 1 3 6 0 1 2 3 4 5 6 7 0 Al treatment (d) Al treatment (d) Q ! *+ 8B (0 Al) 8B 1D (2 ay 7 A l) 10 1D B( ay 0 A l) 10 1D B( ay 27 Al )1 8B D ay (0 Al) 8B 3D (2 ay 7 A l) 10 3D B( ay 0 A l) 10 3D B( ay 27 Al )3 8B D ay (0 Al) 8B 6D (2 ay 7 A l) 10 6D B( ay 0 A l) 10 6D B( ay 27 Al )6 D ay Al: Lines: Duration: - S + - T + - S + - + T - 1 Day 3 Days + + S T 6 Days (8 3> *+ ? ! Temporal Expression Pattern of AltSB Candidate in Root Tips of Al Tolerant and Sensitive NILs Temporal Expression Pattern of AltSB Candidate in Root Tips of Al Tolerant and Sensitive NILs 140 140 Relative Expression Relative Expression 120 100 80 60 40 20 0 120 100 80 60 40 20 0 311 G A11 G 3111 G J B J + + + T 3 Days + S + T + B 8B (0 Al) 8B 1D (2 ay 7 A l) 10 1D B( ay 0 A l) 10 1D B( ay 27 Al )1 8B D ay (0 Al) 8B 3D (2 ay 7 A l) 10 3D B( ay 0 A l) 10 3D B( ay 27 Al )3 8B D ay (0 Al) 8B 6D (2 ay 7 A l) 10 6D B( ay 0 A l) 10 6D B( ay 27 Al )6 D ay S T S 1 Day 6 Days Q ! *+ (8 3> *+ ? ! Q ! *+ 8B (0 Al) 8B 1D (2 ay 7 A l) 10 1D B( ay 0 A l) 10 1D B( ay 27 Al )1 8B D ay (0 Al) 8B 3D (2 ay 7 A l) 10 3D B( ay 0 A l) 10 3D B( ay 27 Al )3 8B D ay (0 Al) 8B 6D (2 ay 7 A l) 10 6D B( ay 0 A l) 10 6D B( ay 27 Al )6 D ay Al: Lines: Duration: Al: Lines: Duration: - + - + - S 1 Day T + + S T 3 Days - + + S T 6 Days (8 3> *+ ? ! Physiology of Sorghum Al Tolerance Al tolerance is Al-Inducible 30 25 20 Root Tip Citrate Efflux is AlInducible and Activated by Al 1200 1000 ATF 10B (Tolerant) ATF 10B (Tolerant) • • • Vera Alves ! " & )* # ,% $ % # ' " % %$ " # $ Root citrate exudation (pmol plant h ) Root growth rate (mm d-1) 15 10 5 0 25 20 15 10 5 0 Control +27 µM Al -1 -1 800 600 400 200 0 1000 800 600 400 200 ATF 8B (Sensitive) • • • + $ $ . % % % $$ $ $ / $ % ( + / - % ($ # ATF 8B (Sensitive) Control + 27 µM Al $ $! ! $ - ! Jon Shaff 1 3 6 - 0 1 2 3 4 5 6 7 0 Al treatment (d) Al treatment (d) $ ; • • • • • • We are working to translate this genomics-based discovery to real-world crop improvement. Sorghum is an important food crop in Africa. We have assembled a diversity panel of 500 sorghum varieties that captures most of the sorghum diversity worldwide. We have phenotyped all 500 sorghum lines for Al tolerance. We also have sequenced the DNA region around SbMATE in all 500 lines. Used statistical genetics-based computational methods (association genetics) to identify DNA sequence polymorphisms (SNPs) that are diagnostic for the most Al tolerant versions (alleles) of SbMATE in sorghum. Have generated easy to score molecular markers from these SNPs, and working with sorghum breeders in Niger and Kenya to genotype their sorghum germplasm. They will use these markers to identify the best SbMATE alleles in their breeding materials, and then use these markers via marker-assisted selection to rapidly breed for enhanced sorghum Al tolerance. • • ...
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This note was uploaded on 10/20/2009 for the course BIO G 1102 taught by Professor Walcott during the Spring '08 term at Cornell University (Engineering School).

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